[cisco-voip] Cisco Security Advisory: Crafted ICMP Messages Can
Cause Denial of Service
Cisco Systems Product Security Incident Response Team
psirt at cisco.com
Tue Apr 12 09:10:44 EDT 2005
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Cisco Security Advisory: Crafted ICMP Messages Can Cause Denial of
Service
Revision 1.0
For Public Release 2005 April 12 1200 UTC (GMT)
+----------------------------------------------------------------------
Contents
========
Summary
Affected Products
Details
Impact
Software Versions and Fixes
Obtaining Fixed Software
Workarounds
Exploitation and Public Announcements
Status of This Notice: FINAL
Distribution
Revision History
Cisco Security Procedures
+----------------------------------------------------------------------
Summary
=======
A document that describes how the Internet Control Message
Protocol (ICMP) could be used to perform a number of Denial of
Service (DoS) attacks against the Transmission Control Protocol
(TCP) has been made publicly available. This document has been
published through the Internet Engineering Task Force (IETF)
Internet Draft process, and is entitled "ICMP Attacks Against TCP"
(draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on
a device itself, can be of three types:
1. Attacks that use ICMP "hard" error messages
2. Attacks that use ICMP "fragmentation needed and Don't Fragment (DF)
bit set" messages, also known as Path Maximum Transmission Unit
Discovery (PMTUD) attacks
3. Attacks that use ICMP "source quench" messages
Successful attacks may cause connection resets or reduction of
throughput in existing connections, depending on the attack type.
Multiple Cisco products are affected by the attacks described in this
Internet draft.
Cisco has made free software available to address these vulnerabilities.
In some cases there are workarounds available to mitigate the effects of
the vulnerability.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml
The disclosure of these vulnerabilities is being coordinated by the
National Infrastructure Security Coordination Centre (NISCC), based in
the United Kingdom. NISCC is working with multiple vendors whose
products are potentially affected. Its posting can be found at:
http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en
Affected Products
=================
Vulnerable Products
+------------------
Cisco IOS
+--------
Cisco products that run Cisco IOS® and that have PMTUD enabled, either
by default or because they have been explicitly configured to do PMTUD,
are affected. All versions of IOS are impacted. The severity of the
exposure depends upon the protocols and applications that rely on
specific ICMP messages to perform PMTUD. IOS is not vulnerable to
attacks that make use of ICMP "hard" error or "source quench" messages.
To determine the software running on a Cisco product, log in to the
device and issue the show version command to display the system banner.
Cisco IOS Software will identify itself as "Internetwork Operating
System Software" or simply "IOS." The image name will be displayed
between parentheses shortly after this identification (possibly in the
next line), followed by "Version" and the IOS release name. Other Cisco
devices will not have the show version command or will give different
output.
The following example identifies a Cisco product running IOS release
12.2(15)T14 with an installed image name of C806-K9OSY6-M:
gw>show version
Cisco Internetwork Operating System Software
IOS (tm) C806 Software (C806-K9OSY6-M), Version 12.2(15)T14, RELEASE SOFTWARE (fc4)
[...]
The following protocols make use of PMTUD and if enabled in the network
may cause IOS devices to be vulnerable to PMTUD attacks.
* Transmission Control Protocol over Internet Protocol (IP) Version 4
: if an IOS device establishes TCP sessions with other devices, for
example, to speak Border Gateway Protocol (BGP) with other peers,
it may be vulnerable to crafted ICMP "fragmentation needed and
Don't Fragment (DF) bit set" error messages if PMTUD is enabled.
PMTUD is disabled by default for TCP in IOS. PMTUD is enabled if
the command ip tcp path-mtu-discovery is present in the device
configuration.
* Transmission Control Protocol over Internet Protocol Version 6
(IPv6): PMTUD is enabled by default for IPV6; therefore, devices
configured for IPv6 are vulnerable to PMTUD attacks if they are
running services that rely on TCP, like BGP. If the device is just
forwarding IPv6 traffic, i.e., it does not establish TCP sessions
with other hosts, then it is not affected.
* IP Security (IPSec): when an IOS device is configured to use IPSec,
PMTUD is enabled by default, and therefore, the device may be
affected by the PMTUD attack described in this document. An IOS
device is configured for IPSec if either crypto map or tunnel
protection is applied to an interface. For example:
crypto ipsec profile IPSEC_PROFILE
[...]
!
crypto map MYMAP 1 ipsec-isakmp
[...]
!
interface Tunnel0
tunnel protection ipsec profile IPSEC_PROFILE
[...]
!
interface Ethernet1
crypto map MYMAP
[...]
* Generic Routing Encapsulation (GRE) and IPinIP: devices configured
to use these tunneling protocols are vulnerable to crafted ICMP
"fragmentation needed and DF bit set" messages if PMTUD is enabled.
PMTUD is disabled by default for these two protocols. The device is
vulnerable if the command tunnel path-mtu-discovery is present in
the configuration.
* Layer 2 Tunneling Protocol Version 2 (L2TP) and Layer 2 Tunneling
Protocol Version 3(L2TPv3): devices configured to use these
tunneling protocols are vulnerable to crafted ICMP "fragmentation
needed and DF bit set" messages if PMTUD is enabled. PMTUD is
disabled by default for these protocols. A device running L2TP is
vulnerable if the command ip pmtu appears in the device's
configuration.
Note: L2TP (version 2) and L2TPv3 (version 3) are two different
and independent protocols. Both are affected, but throughout the
rest of this document we will refer to them as one since they are
affected in the same manner.
In addition to IOS-based routers, the following devices also run Cisco
IOS or software based on Cisco IOS and are therefore vulnerable:
* The Catalyst 4000 and 6000 switches when running IOS in either
hybrid (Supervisor Engine running CatOS and Multilayer Switch
Feature Card running IOS) or native mode (Supervisor Engine running
IOS.)
* Cisco Aironet Wireless LAN Access Points and Bridges.
* Catalyst 2900XL, 2900XL-LRE, 3500XL, 2940, 2950, 2950-LRE, 2955,
and 2970 series switches.
* Catalyst 2948G-L3, 3550, 3560, 3750, and 3750-ME series switches.
* The Communication Media Module (CMM)
* Cisco Optical Network Solutions (ONS) products: the ML and SL
blades in the ONS 15454, and the ONS 15530/15540.
* Cisco DistributedDirector.
Non-IOS Products
+---------------
The following non-IOS-based products are also vulnerable:
* Cisco CRS-1: the CRS-1 runs IOS XR, which is vulnerable to PMTUD
attacks and to attacks that use ICMP "hard" error messages if the
CRS-1 establishes TCP sessions with other devices in applications
like BGP. PMTUD is disabled by default in IOS XR. PMTUD is enabled
if the command tcp path-mtu-discovery is present in the device
configuration. Use the show version command to obtain the version
of the running IOS XR software.
* Cisco PIX Security Appliance is vulnerable to PMTUD attacks if it
is configured to use IPSec. IPSec is not enabled by default on the
Cisco PIX Security Appliance. The Cisco PIX Security Appliance is
using IPSec if the device configuration shows a crypto map applied
to an interface through the command crypto map <crypto map name>
interface <interface name>. The show version command can be used to
determine the running version of the Cisco PIX Security Appliance
software. Please note that version 7.0 and later of the PIX
Security Appliance software is not affected by these
vulnerabilities.
* Cisco IP Phones
+ 7940/7960 with Skinny Client Control Protocol (SCCP) firmware.
+ 7940/7960 with Session Initiation Protocol (SIP) firmware.
+ 7970 with Skinny Client Control Protocol firmware (vulnerable
only to crafted ICMP hard error messages)
The version of the firmware running on your Cisco IP Phone can be
found by pressing the "Settings" button of your phone and selecting
the "Status" menu options.
* Cisco Catalyst 6608 Voice Gateway and Cisco 6000 FXS Analog
Interface Module (WS-X6624-FXS) are vulnerable to crafted ICMP hard
errors, as well as to crafted ICMP "source quench" messages. To
obtain the version of the 6608 and 6624 firmware, log in to your
Catalyst 6500 series switch and issue the show version command.
* Cisco 11000 and 11500 Content Services Switches (CSS).
* Global Site Selector (GSS).
* Cisco ONS products: ONS 15302 and ONS 15305.
* Cisco MDS 9000 Series Multilayer Switches.
* VPN 5000 concentrator.
Products Confirmed Not Vulnerable
+--------------------------------
The following products are not vulnerable:
* Cisco Firewall Services Module (FWSM) for Cisco Catalyst 6500
Series and Cisco 7600 Series.
* Cisco Guard and Cisco Traffic Anomaly Detector Denial of Service
mitigation appliances.
* Catalyst Switches. The following Catalyst switches do not run Cisco
IOS and therefore are not affected by the vulnerabilities described
in this document:
+ 1200
+ 1700
+ 1900
+ 2100
+ 28xx
+ 2948G-GE-TX
+ 2900, 2902, 2926T and 2926G
+ 3000, 3100, 3200
+ 3900
+ 5000
+ The Catalyst 4000 and 6000 switches can run CatOS or IOS. When
running CatOS, they are not vulnerable unless a Multilayer
Switch Feature Card (MSFC) is present (since the MSFC runs
IOS.) When running IOS, they are vulnerable as described above
in the Vulnerable Products section.
* Cisco ONS products: ONS 15327 Metro Edge Optical Transport
Platform, ONS 15454 Optical Transport Platform (MSPP and MSTP), ONS
15531/15532 T31 OMDS Metro WDM System, ONS 15216 EDFA3/EDFA2/OADM,
ONS 15310 CL.
* Cisco IP Phones
+ ATA 186/188
+ 7910
+ 7912
* Cisco VG248 Analog Phone Gateway
* Cisco MeetingPlace
* Cisco VPN 3000 Series Concentrators, VPN 3002 Hardware Clients, and
the VPN Software Client (please note that the VPN Software Client
itself is not vulnerable but the operating system the VPN clients
runs on may be vulnerable. Please check with your operating system
vendor.)
* Cisco BTS 10200 Softswitch
* Content Engines, Content Routers, and Content Distribution Managers
running Cisco Application and Content Networking System (ACNS)
software.
The following voice and IP communication products are shipped with,
and run on top of, the Microsoft Windows operating system. However,
the current customization of Microsoft Windows made by Cisco (release
2000-2-6) and included with these products has PMTUD disabled by
default. These products may be vulnerable if PMTUD has been enabled by
the end user and if Microsoft Windows is affected by the ICMP issues
described in this document:
* Cisco Call Manager
* Cisco IP Interactive Voice Response
* Cisco IP Call Center Express
* Cisco IP Queue Manager
* Cisco Personal Assistant
* Cisco Emergency Responder
* Cisco Conference Connection
* Cisco Internet Service Node
The following products use non-Cisco-customized versions of Microsoft
Windows. PMTUD is enabled by default on Microsoft Windows, so these
products may be vulnerable if this default setting has not been changed
and if Microsoft Windows is affected by the ICMP issues described in
this document:
* Cisco Unity
* Cisco IP Contact Center Enterprise Edition
* Cisco Secure ACS Solution Engine, also known as the Cisco Secure
ACS Appliance
To verify whether PMTUD is enabled in the version of Microsoft Windows
used by your Cisco product, please check the value of the following
registry key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters\EnablePMTUDiscovery
No other Cisco products are currently known to be affected by these
vulnerabilities.
For all Cisco products that are based on a third-party Operating System
and when Cisco is not supplying the OS, please contact the respective
vendor for the appropriate vulnerability assessment. It is important
to take into consideration that a Cisco product may be impacted if the
underlying, non-Cisco operating system is vulnerable.
Summary of Vulnerable Products
+-----------------------------
The following table summarizes how Cisco products are affected by the
vulnerabilities described in this document:
+-----------------------------------------------+
| Product | Hard | PMTUD | Source |
| | Error | | Quench |
|--------------+----------+----------+----------|
| IOS | Not | Affected | Not |
| | affected | | affected |
|--------------+----------+----------+----------|
| IOS XR | Affected | Affected | Not |
| | | | affected |
|--------------+----------+----------+----------|
| IP Phones | Affected | Affected | Affected |
|--------------+----------+----------+----------|
| Cisco PIX | Not | | Not |
| Security | affected | Affected | affected |
| Appliance | | | |
|--------------+----------+----------+----------|
| Catalyst | | Not | |
| 6608 and | Affected | affected | Affected |
| 6624 | | | |
|--------------+----------+----------+----------|
| Cisco 11000 | Not | Not | Affected |
| and 11500 | affected | affected | |
|--------------+----------+----------+----------|
| Cisco GSS | Not | Not | Affected |
| | affected | affected | |
|--------------+----------+----------+----------|
| MDS 9000 | Not | Not | Affected |
| | affected | affected | |
|--------------+----------+----------+----------|
| Cisco VPN | Not | | Not |
| 5000 | affected | Affected | affected |
| Concentrator | | | |
|--------------+----------+----------+----------|
| Some ONS | Not | Affected | Not |
| products | affected | | affected |
+-----------------------------------------------+
Please refer to the Details section for additional information since
within one product family different models may be affected differently.
Details
=======
The Internet Control Message Protocol is an integral part of the
Transmission Control Protocol/Internet Protocol (TCP/IP) protocol
suite that is used to report error conditions and provide diagnostic
information. ICMP error messages can be generated by both end systems
and intermediate systems, i.e., routers. End systems and intermediate
systems react to error messages received via ICMP in different ways
depending on the type of error that is being reported. The types of
errors that can be reported via ICMP fall into two categories: "soft"
errors and "hard" errors.
RFC 1122 ("Requirements for Internet Hosts - Communications Layers"
- - http://www.ietf.org/rfc/rfc1122.txt), defines three "hard" errors
("protocol unreachable", "port unreachable", and "fragmentation
needed and Don't Fragment bit set") and five "soft" errors ("network
unreachable", "host unreachable", "source route failed", "time
exceeded", and "parameter problem".) "Source quench" is another ICMP
error message that can be generated by Internet hosts, and while RFC
1122 does not clearly classify it as "soft" or "hard", it should be
considered as a soft error because of the way this message type should
be handled by hosts that receive it: hosts should cut back for a period
of time the rate at which they are sending data to the host that
generated the ICMP "source quench" message, and then gradually increase
the transmission rate again.
It is important to note that the "fragmentation needed and Don't
Fragment bit set" (type 3, code 4) message is used by an important
mechanism called Path MTU Discovery, documented in RFC 1191 ("Path
MTU discovery" - http://www.ietf.org/rfc/rfc1191.txt). PMTUD allows
some protocols of the TCP/IP protocol suite to dynamically find the
MTU of a path so IP fragmentation is minimized and bandwidth can be
used more efficiently. This mechanism is not mandatory for Internet
hosts, but those that implement it need to treat ICMP "fragmentation
needed and DF bit set" messages as "soft" errors. A good reference to
understand how IP fragmentation works and the role that PMTUD plays
in reducing fragmentation is the Cisco white paper "IP Fragmentation
and PMTUD", available at
http://www.cisco.com/en/US/tech/tk827/tk369/technologies_white_paper09186a00800d6979.shtml.
Making a distinction between the types of errors ("soft" versus "hard")
that can be reported via ICMP is important because it dictates how
Internet hosts will respond to them. In general, connection-oriented
protocols like TCP should abort an existing connection in response to
an ICMP "hard" error message, and Internet hosts should try to correct
the error condition that elicited the receipt of an ICMP "soft" error
message.
An IETF Internet Draft entitled "ICMP Attacks Against TCP"
(draft-gont-tcpm-icmp-attacks-03.txt) that describes how the ICMP
protocol can be used to perform a number of Denial of Service attacks
against the TCP protocol has been made publicly available. These attacks
require knowledge of the IP addresses and ports (in the case of TCP)
that two Internet hosts are using to communicate with each other and
can cause connection resets and reduction of throughput in existing
connections.
Note: these attacks only affect sessions terminating or originating on a
device itself, not transit traffic; i.e., traffic that passes through a
device, but is destined elsewhere is not affected.
Attacks Based on Crafted Hard ICMP Error Messages
+------------------------------------------------
Upon receipt of a "hard" ICMP error message, an Internet host must
abort the connection with the host to which the ICMP error message
applies. This host is not necessarily the system that generated the
ICMP message, but it is uniquely identified through the IP header and
transport protocol data embedded in the ICMP payload. The reason for
this is that "hard" errors represent serious network problems for which
there is not a possibility for recovery. Crafted "hard" ICMP error
messages could cause an Internet host to incorrectly abort an existing
connection when in reality there are no network problems. This type
of attack is classified as a "blind connection-reset" attack in the
Internet Draft draft-gont-tcpm-icmp-attacks-03.txt.
PMTUD Attacks
+------------
Crafted "fragmentation needed and DF bit set" ICMP messages can be used
to set a connection's Path MTU to a very low, impractical value, if an
Internet host is performing PMTUD. This value can cause higher layer
protocols to start timing out because of a very low throughput, even
though the connection is still in the established state. This type of
attack is classified as a "throughput-reduction" attack in the Internet
Draft draft-gont-tcpm-icmp-attacks-03.txt.
Per the PMTUD algorithm described in RFC 1191, implementations must
"age" cached MTU values, which means that the MTU will go back to
its optimum size, a process that can take up to 10 minutes (RFC 1191
suggests 10 minutes, but this is not a requirement and therefore it is
implementation-dependent.) Please note, however, that if an attacker
continues to send crafted ICMP "fragmentation needed and DF bit set"
messages to a vulnerable host, the cached MTU will never age, causing a
continuous denial-of-service condition.
As mentioned before, the ICMP "fragmentation needed and DF bit set"
message is considered a "hard" error per RFC 1122 if the Internet host
receiving it is not performing PMTUD. This means that a PMTUD attack
also has the potential to cause a connection reset.
For protocols that make use of a "transport layer" MTU to minimize the
risk of fragmentation, like TCP and its Maximum Segment Size (MSS)
variable, a good way to determine if a connection is suffering from a
successful attack is to monitor the value of this "transport layer"
MTU - an unreasonably low value may indicate that an attack has been
performed. An example of how to do this in Cisco IOS will be provided
later in this document.
Note: several common protocols make use of TCP, and therefore may be
affected by PMTUD attacks. Some examples include BGP, the Hyper Text
Transfer Protocol (HTTP - used in the World Wide Web), the Simple Mail
Transfer Protocol (SMTP - used for transferring electronic mail), and
Secure Shell (SSH). Some protocols in the IBM suite like Data-Link
Switching (DLSw), Serial Tunneling (STUN), and Block Serial Tunneling
(BSTUN) can be configured to use TCP as their transport protocol. The
Domain Name System (DNS) normally uses User Datagram Protocol (UDP) but
in some situations (large zone transfers, for example) it also uses TCP.
Attacks Based on Crafted Source Quench ICMP Messages
+---------------------------------------------------
As mentioned before, Internet hosts are supposed to cut back the rate
at which they send data to another host that generated an ICMP "source
quench" message. While the actual response to an ICMP "source quench"
message varies by TCP/IP implementation and by the transport layer
protocol in use, in general, hosts receiving an ICMP "source quench"
message should trigger a congestion avoidance algorithm.
In the case of a host using TCP to communicate with another,
if an ICMP "source quench" message is received the recommended
procedure per RFC 1122 is to trigger a "slow start", as if a
retransmission timeout had occurred. RFC 2001 ("TCP Slow Start,
Congestion Avoidance, Fast Retransmit, and Fast Recovery Algorithms"
- - http://www.ietf.org/rfc/rfc2001.txt) describes the "slow start" and
"congestion avoidance" algorithms used in modern implementations of TCP
and states that in practice, the "slow start" and "congestion avoidance"
algorithms are implemented together.
The lower rate at which the sending host transmits data allows the host
that generated the ICMP "source quench" message to process and empty its
receive buffers.
Crafted "source quench" ICMP messages can be used to decrease the
rate at which a host is sending data. While over time, as long as no
additional Source Quench messages are received, the window size will
increase to a reasonable value, a crafted "source quench" message
can potentially reduce communication efficiency significantly. If an
attacker succeeds in periodic transmission of crafted ICMP "source
quench" messages to a vulnerable device, a prolonged degradation of
service for that connection may occur.
This type of attack is classified as a "throughput-reduction" attack in
the Internet Draft draft-gont-tcpm-icmp-attacks-03.txt.
How Cisco Products Are Affected
+------------------------------
Different Cisco products are affected in different ways to the ICMP
attacks described in this document. In some cases, some products are
affected when specific configurations or network protocols are in use.
What follows is a description of how vulnerable products are affected
and under what configurations. Information about specific Cisco bug IDs
for each product is presented.
Cisco IOS
+--------
Cisco IOS is not vulnerable to attacks that make use of ICMP "hard"
error messages because IOS checks whether a connection is in the
"established" state, and takes action only for connections in the
"non-established" state.
In addition, IOS does not process ICMP "source quench" messages and
therefore, is not vulnerable to attacks that are based on crafting this
type of message.
IOS is vulnerable to PMTUD attacks as described in the Vulnerable
Products section. This means that an attacker could change the Path
MTU by crafting an ICMP "fragmentation needed and DF bit set" message
("packet too big" message in the case of IPv6.) The following list
provides the Cisco bug IDs for the PMTUD vulnerabilities in different
protocols in IOS:
* All protocols that make use of PMTUD: CSCef60659 -- More stringent
checks required for ICMP unreachables.
* Transmission Control Protocol over Internet Protocol Version 4:
CSCed78149 -- TCP connections over IP version 4 doing PMTUD are
vulnerable to crafted ICMP packets.
A good way to verify whether a connection is suffering from the
effects of a PMTUD attack is by looking at the MSS value of the
connection. For BGP sessions the command "show ip bgp neighbors |
include data segment" will display the MSS (denoted as "max data
segment"), as in the following example:
Router#show ip bgp neighbors | include data segment
Datagrams (max data segment is 1460 bytes):
Router#
The official minimum MTU is 68 bytes, although in today's Internet
a MSS less than 576 bytes should be considered suspicious. Section
7 of RFC 1191 contains a list of common MTU values used on the
Internet.
For other TCP connections, the Transmission Control Block (TCB) of
a specific connection must be determined using the command show tcp
brief, and then this TCB must be used in the command show tcp tcb
<TCB identified with show tcp brief> | include data segment, which
will display the MSS (denoted again as max data segment):
Router#show tcp brief
TCB Local Address Foreign Address (state)
00E97148 192.168.100.1.23 192.168.100.1.11002 TIMEWAIT
00E97A78 192.168.100.1.23 192.168.100.1.11003 ESTAB
00E975E0 192.168.100.1.11003 192.168.100.1.23 ESTAB
Router#show tcp tcb 0x00E975E0 | include data segment
Datagrams (max data segment is 1474 bytes):
Router#
Please note that this technique can also be used for TCP over IPv6.
* Transmission Control Protocol over Internet Protocol Version 6:
CSCef61610 -- Incorrect handling of ICMPv6 messages can cause TCP
performance problems.
* IPSec: CSCsa59600 -- IOS IPSec connections may be vulnerable to
crafted ICMP packets which may cause IPSec to use very small PMTU
values for a given flow. After the PMTU has been decreased by a
crafted ICMP "fragmentation needed and DF bit set" message, if no
additional ICMP "fragmentation needed and DF bit set" messages are
received, the learned MTU will be active for 10 minutes, after which
the PMTU is restored to the first-hop data-link MTU, per RFC 1191.
A way to verify whether an IPSec tunnel is suffering from the
effects of a PMTUD attack is by running the command "show crypto
ipsec sa | include mtu", as in the following example:
Router#show crypto ipsec sa | include mtu
path mtu 1500, media mtu 1500
Router#
* Generic Routing Encapsulation and IPinIP: CSCef44699 -- GRE and
IPinIP tunnels may be vulnerable to crafted ICMP packets.
A way to verify whether a GRE or IPinIP tunnel is suffering from the
effects of a PMTUD attack is by running the command "show interface
tunnel <number> | include Path MTU", as in the following example:
Router#show interface tunnel 0 | include Path MTU
Path MTU Discovery, ager 10 mins, MTU 1476, expires never
* Layer 2 Tunneling Protocol Version 2 and Layer 2 Tunneling Protocol
Version 3: for L2TP version 2 the Cisco bug ID is CSCsa52807 (
registered customers only) -- L2TPv2 doing PMTUD vulnerable to
spoofed ICMP packets. For L2TP version 3 the bug ID is CSCef43691 (
registered customers only) -- Connections using Layer 2 Tunneling
Protocol v3 (L2TPv3) and doing PMTU discovery may be vulnerable to
crafted ICMP packets.
A way to verify whether a L2TPv2 session is suffering from the
effects of a PMTUD attack is by running the command show vpdn
session all | include Session MTU, as in the following example:
Router#show vpdn session all | include Session MTU
Session MTU is 40 bytes
For L2TPv3, a PMTUD attack can be identified by running the command
show l2tun session all | include PMTU, as in the following example:
Router#show l2tun session all | include Session MTU
Session PMTU enabled, path MTU is 32 bytes
Session PMTU enabled, path MTU is 32 bytes
Session PMTU enabled, path MTU is 32 bytes
IOS XR
+-----
IOS XR is vulnerable to attacks based on ICMP "hard" error messages,
as well as to PMTUD attacks. The Cisco Bug ID that documents this
vulnerability is CSCef45332 -- CRS-1 connections may be vulnerable to
crafted ICMP packets. IOS XR does not process ICMP "source quench"
messages, so it is not vulnerable to attacks based on this type of
message.
Cisco IP Phones
+--------------
Different models of Cisco IP Phones are vulnerable to attacks based on
ICMP "hard" error messages, ICMP "source quench" messages, and/or PMTUD
attacks.
* CSCef46728 -- 7940/7960 IP Phone with SCCP firmware may be
susceptible to crafted ICMP "hard" error messages.
* CSCef54947 -- 7970 IP Phone with SCCP firmware may be susceptible to
crafted ICMP "hard" error messages.
* CSCef54204 -- 7940/7960 IP Phone with SIP firmware may be vulnerable
to crafted ICMP "source quench" error messages. Please note that
a 7940/7960 IP Phone with SIP firmware does not support TCP for
signaling, so only telnet sessions into the phone (for management)
and short-lived HTTP sessions from the phone (to servers providing
directory services, for example) are affected by this vulnerability.
* CSCef54206 -- 7940/7960 IP Phone with SIP firmware may be vulnerable
to crafted ICMP "hard" error messages. Please note that a 7940/7960 IP
Phone with SIP firmware does not support TCP for signaling, so only
telnet sessions into the phone (for management) and short-lived HTTP
sessions from the phone (to servers providing directory services, for
example) are affected by this vulnerability.
Cisco PIX Security Appliance
+---------------------------
A PIX Security Appliance with IPSec configured will actively participate
in PMTUD per RFC 1191 and RFC 2401 ("Security Architecture for the
Internet Protocol" - http://www.ietf.org/rfc/rfc2401.txt). This means
that the PIX Security Appliance can dynamically discover and adjust its
path MTU for a given IPSec flow when it receives an ICMP "fragmentation
needed and DF bit set" message.
Under this scenario, the PIX Security Appliance is also vulnerable to
crafted ICMP type 3 code 4 messages that try to set the path MTU to a
very low value. This vulnerability is documented in the Cisco Bug ID
CSCef57566 -- A PIX Security Appliance with IPSec configured can be
susceptible to crafted ICMP packets suggesting a very small PMTU for a
path or a Security Association. This symptom is observed when IPSec is
configured for PMTUD, which is turned on automatically when IPSec is
configured on the PIX Security Appliance.
Catalyst 6608 and 6624
+---------------------
The Cisco Catalyst 6608 Voice Gateway and Cisco 6000 FXS Analog
Interface Module (WS-X6624-FXS) are vulnerable to attacks based on
ICMP "hard" error and "source quench" messages. The Cisco Bug ID that
documents this vulnerability is CSCsa60692 -- ICMP Hard error handling.
Cisco 11000 and 11500 Content Services Switches
+----------------------------------------------
The Cisco 11000 and 11500 Content Services Switches are vulnerable to
attacks based on ICMP "source quench" messages on the management port;
they are not vulnerable on the network ports. The CSS does not perform
PMTUD and therefore is not vulnerable to PMTUD attacks. The Cisco Bug
ID that documents the vulnerability to ICMP "source quench" messages is
CSCeh45454 -- ICMP error packet attacks against TCP.
Cisco Global Site Selector
+-------------------------
The Cisco Global Site Selector version 1.1 and earlier is vulnerable to
attacks based on ICMP "source quench" messages. It is not vulnerable to
attacks based on ICMP "hard error" messages or to PMTUD attacks. The
Cisco Bug ID that documents the vulnerability to ICMP "source quench"
messages is CSCeh20083 -- ICMP error packet attacks against TCP.
Cisco MDS 9000 Series Multilayer Switches
+----------------------------------------
The Cisco MDS 9000 Series Multilayer Switch is vulnerable to PMTUD
attacks. The Cisco Bug ID that documents this vulnerability is
CSCeh04183 -- ICMP attacks against TCP.
Cisco ONS Products
+-----------------
The affected Cisco ONS products are vulnerable to PMTUD attacks only.
VPN 5000 Concentrator
+--------------------
The VPN 5000 concentrator is vulnerable to PMTUD. ICMP "source quench"
messages are only processed to keep message counts, but not for avoiding
congestion. Therefore, this device is not vulnerable to attacks based
on this type of messages. The Cisco Bug ID that documents the PMTUD
vulnerability is CSCeh59823 -- ICMP 3/4 messages may affect IPSec
sessions.
Impact
======
Successful exploitation of attacks using crafted ICMP "hard" error
messages may result in connections being dropped.
Successful exploitation of attacks based on "fragmentation needed and
DF bit set" (or PMTUD attacks) and ICMP "source quench" error messages
may result in connections being throttled to very low throughput. While
throughput is low, the output buffer of a sending host could overflow
or packets could be dropped or be unnecessarily fragmented, which may
affect applications and communication efficiency. Accordingly, crafted
ICMP packets could interfere with network protocols, such as the Border
Gateway Protocol, Label Distribution Protocol (LDP) and DLSw.
In addition to causing low throughput, a PMTUD attack can also cause
high Central Processing Unit (CPU) utilization and extra memory
consumption on the receiving host because the CPU will spend time and
memory buffers to reassemble the incoming fragmented packets.
In all cases, these attacks may result in Denial-of-Service conditions.
No remote code execution or unauthorized access results from these types
of attacks.
Software Versions and Fixes
===========================
When considering software upgrades, please also consult
http://www.cisco.com/en/US/products/products_security_advisories_listing.html
and any subsequent advisories to determine exposure and a complete
upgrade solution.
In all cases, customers should exercise caution to be certain the
devices to be upgraded contain sufficient memory and that current
hardware and software configurations will continue to be supported
properly by the new release. If the information is not clear, contact
the Cisco Technical Assistance Center ("TAC") for assistance.
IOS-based Products
+-----------------
Each row of the Cisco IOS software table (below) describes a release
train and the platforms or products for which it is intended. If a given
release train is vulnerable, then the earliest possible releases that
contain the fix (the "First Fixed Release") and the anticipated date
of availability for each are listed in the "Rebuild" and "Maintenance"
columns. A device running a release in the given train that is earlier
than the release in a specific column (less than the First Fixed
Release) is known to be vulnerable. The release should be upgraded at
least to the indicated release or a later version (greater than or equal
to the First Fixed Release label).
For further information on the terms "Rebuild" and "Maintenance" please
consult the following URL:
http://www.cisco.com/warp/public/620/1.html
Due to differences in software availability and in the feature scenarios
in which Cisco IOS is vulnerable, the table of first fixed releases has
been broken down based on the different vulnerabilities that affect each
technology. There are four different groups:
1. TCPv4: represents CSCed78149 and CSCef60659. The first Cisco Bug ID
tracks TCP's vulnerability to PMTUD attacks, and the second Cisco Bug
ID tracks the vulnerability that affects all protocols that make use of
PMTUD, with the exception of TCP over IPv6, which is not affected by
this vulnerability.
2. Tunnels: represents CSCef60659, CSCef43691, CSCsa61864, CSCsa59600,
and CSCef44699. These are the Cisco Bug IDs that track vulnerabilities
in most of the affected tunneling protocols (GRE, L2TPv3, and IPSec.)
3. TCPv6: represents CSCef61610, which is the Cisco Bug ID that tracks
TCP's vulnerability to PMTUD attacks when running over IPv6.
4. L2TPv2: represents CSCsa52807, which is the Cisco Bug ID that tracks
L2TPv2's vulnerability to PMTUD attacks.
+-----------------------------------------------+
| Major Release | Availability of Repaired |
| | Releases |
|-------------------+---------------------------|
| Affected | | |
| 12.0-Based | Rebuild | Maintenance |
| Release | | |
|-------------------+-------------+-------------|
| | TCPv4 | | |
| | and | 12.0(28c) | |
| | Tunnels | | |
|12.0 |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(12)DA8 or later |
| | Tunnels | |
|12.0DA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.0DB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(15)BC2f or later |
| | Tunnels | |
|12.0DC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | | 12.0(27)S5, | |
| | | available | |
| | | 23-May-05 | |
| |TCPv4 |-------------|12.0(31)S, |
| | and | 12.0(28)S3, | available |
| | Tunnels | available | 28-Apr-05 |
| | | 25-Apr-05 | |
| | |-------------| |
| | | 12.0(30)S1 | |
| |---------+-------------+-------------|
| 12.0S | | 12.0(27)S5, | |
| | | available | |
| | | 23-May-05 | |
| | |-------------|12.0(31)S, |
| | TCPv6 | 12.0(28)S3, | available |
| | | available | 28-Apr-05 |
| | | 25-Apr-05 | |
| | |-------------| |
| | | 12.0(30)S1 | |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(15)BC2f or later |
| | Tunnels | |
|12.0SC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.0S or later |
| | Tunnels | |
|12.0SL |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.0S or later |
| | Tunnels | |
|12.0SP |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.0S or later |
| | Tunnels | |
|12.0ST |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.0SX |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.0S or later |
| | Tunnels | |
|12.0SZ |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.0S or later |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0T |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | | 12.0(25)W5 | |
| | TCPv4 | (27c) | |
| |and |-------------| |
| | Tunnels | 12.0(28)W5 | |
| 12.0W5 | | (31a) | |
| |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | 12.0(5) | |
| | and | WC12, | |
| | Tunnels | available | |
| 12.0WC | | 25-July-05 | |
| |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XD |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1E latest |
| | Tunnels | |
|12.0XE |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XF |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XG |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XH |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XI |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XJ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.0XK |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.0XL |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XM |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XN |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XQ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.0XR |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1E latest |
| | Tunnels | |
|12.0XS |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(27) or later |
| | Tunnels | |
|12.0XV |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|-------------------+---------------------------|
| Affected | | |
| 12.1-Based | Rebuild | Maintenance |
| Release | | |
|-------------------+-------------+-------------|
| | TCPv4 | | |
| | and | | 12.1(27) |
| | Tunnels | | |
|12.1 |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1AA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(25)EY or later |
| | Tunnels | |
|12.1AX |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(22)EA4 or later |
| | Tunnels | |
|12.1AZ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(12)DA8 or later |
| | Tunnels | |
|12.1DA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.1DB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(15)BC2f or later |
| | Tunnels | |
|12.1DC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | | 12.1(22)E6, | |
| | | available | |
| | | TBD | |
| |TCPv4 |-------------| |
| | and | 12.1(23)E4, | |
| | Tunnels | available | |
| 12.1E | | 8-Apr-05 | |
| | |-------------| |
| | | 12.1(26)E1 | |
| |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.1(22)EA4 | |
| | Tunnels | | |
|12.1EA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.1EB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(15)BC2f or later |
| | Tunnels | |
|12.1EC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | 12.1(19) | |
| | and | EO4, | |
| | Tunnels | available | |
| 12.1EO | | 26-May-05 | |
| |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(20)EU or later |
| | Tunnels | |
|12.1EU |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.1EV |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(18)EW3 or later |
| | Tunnels | |
|12.1EW |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1E latest |
| | Tunnels | |
|12.1EX |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1E latest |
| | Tunnels | |
|12.1EY |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1T |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XD |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1E latest |
| | Tunnels | |
|12.1XE |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XF |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XG |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XH |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(28) or later |
| | Tunnels | |
|12.1XI |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XJ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XL |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XM |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XP |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XQ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XR |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XT |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XU |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1XV |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YD |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YE |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YF |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YH |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.1YI |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.1(22)EA4 or later |
| | Tunnels | |
|12.1YJ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|-------------------+---------------------------|
| Affected | | |
| 12.2-Based | Rebuild | Maintenance |
| Release | | |
|-------------------+-------------+-------------|
| | TCPv4 | | |
| | and | | 12.2(28) |
| | Tunnels | | |
|12.2 |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2B | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(15) | |
| | and | BC2f | |
| | Tunnels | | |
|12.2BC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2BW |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2BY |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | | 12.3(7)XI3 |
| |---------+---------------------------|
| | Tunnels | Vulnerable; migrate to |
| 12.2BZ | | 12.3(7)XI4, available TBD |
| |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(15) | |
| | and | BC2f | |
| | Tunnels | | |
|12.2CX |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(15) | |
| | and | BC2f | |
| | Tunnels | | |
|12.2CY |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; | |
| | and | contact TAC | |
| | Tunnels | | |
|12.2CZ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(12)DA8 | |
| | Tunnels | | |
|12.2DA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2DD |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2DX |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | | 12.2(20)EU |
| | Tunnels | | |
|12.2EU |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(18)EW3 | |
| | Tunnels | | |
|12.2EW |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(25)EWA | |
| | Tunnels | | |
|12.2EWA |---------+-------------+-------------|
| | TCPv6 | 12.2(25)EWA | |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(25)SEB or later |
| | Tunnels | |
|12.2EX |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(25)EY | |
| | Tunnels | | |
|12.2EY |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(4)JA |
| | Tunnels | |
|12.2JA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.2JK |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.2MB |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T |
| | Tunnels | |
| |---------+---------------------------|
| 12.2MC | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T |
|---------+---------+---------------------------|
| | | 12.2(14)S13 | |
| | |-------------| |
| | TCPv4 | 12.2(18)S8 | |
| |and |-------------| |
| | Tunnels | 12.2(20)S7 | |
| | |-------------| |
| 12.2S | | 12.2(25)S3 | |
| |---------+-------------+-------------|
| | | 12.2(20)S7 | |
| |TCPv6 |-------------| |
| | | 12.2(25)S3 | |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(25)SEB | |
| | Tunnels | | |
|12.2SE |---------+---------------------------|
| | TCPv6 | 12.2(25)SEA vulnerable; |
| | | migrate to 12.2(25)SEB |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(18)SO1, available |
| | and | 25-Mar-05 |
| | Tunnels | |
|12.2SO |---------+---------------------------|
| | TCPv6 | 12.2(18)SO2, available |
| | | 29-Apr-05 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.2SU |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(25)S3 |
| | Tunnels | |
|12.2SV |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.2SW |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(17d)SXB7 |
| | Tunnels | |
|12.2SX |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.2(17d)SXB7 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(17d)SXB7 |
| | Tunnels | |
|12.2SXA |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.2(17d)SXB7 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(17d) | |
| | and | SXB7 | |
| | Tunnels | | |
|12.2SXB |---------+-------------+-------------|
| | TCPv6 | 12.2(17d) | |
| | | SXB7 | |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(18) | |
| | and | SXD4 | |
| | Tunnels | | |
|12.2SXD |---------+-------------+-------------|
| | TCPv6 | 12.2(18) | |
| | | SXD4 | |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(17d)SXB7 |
| | Tunnels | |
|12.2SY |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.2(17d)SXB7 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(20)S7 |
| | Tunnels | |
|12.2SZ |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.2(20)S7 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(15)T15 | |
| | Tunnels | | |
|12.2T |---------+-------------+-------------|
| | TCPv6 | 12.2(15)T15 | |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2XC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XD |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XE |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(15)BC2f |
| | Tunnels | |
|12.2XF |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XG |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XH |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XI |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XJ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XK |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XL |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XM |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XN |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XQ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(4)JA |
| | Tunnels | |
|12.2XR |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XT |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XU |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2XW |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.2(4)YA9 | |
| | Tunnels | | |
|12.2YA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2YB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2YC |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YD |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2S or later |
| | Tunnels | |
|12.2YE |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.2S or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2YF |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2YG |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2YH |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
|12.2YJ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YK |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YL |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YM |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YN |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(17d)SXB7 |
| | Tunnels | |
|12.2YO |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YQ |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YR |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2YT | TCPv6 | Vulnerable; migrate to |
| | | 12.3(12) or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2YU | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2YV | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YW |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.2YX |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2YY |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(20)S7 |
| | Tunnels | |
|12.2YZ |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.2(20)S7 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.2(17d)SXB7 |
| | Tunnels | |
|12.2ZA |---------+---------------------------|
| | TCPv6 | Vulnerable; migrate to |
| | | 12.2(17d)SXB7 |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
|12.2ZB |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZC | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZD | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(13) or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZE | TCPv6 | Vulnerable; migrate to |
| | | 12.3(12) or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3 or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZF | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZG | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(13) | |
| | and | ZH6, | |
| | Tunnels | available | |
| | | TBD | |
| |---------+-------------+-------------|
| | | 12.2(13) | |
| 12.2ZH | TCPv6 | ZH6, | |
| | | available | |
| | | TBD | |
| |---------+-------------+-------------|
| | | 12.2(13) | |
| | L2TPv2 | ZH6, | |
| | | available | |
| | | TBD | |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZJ | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZK | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | 12.2(15) | |
| | and | ZL2, | |
| | Tunnels | available | |
| | | TBD | |
| |---------+-------------+-------------|
| | | 12.2(15) | |
| 12.2ZL | TCPv6 | ZL2, | |
| | | available | |
| | | TBD | |
| |---------+-------------+-------------|
| | | 12.2(15) | |
| | L2TPv2 | ZL2, | |
| | | available | |
| | | TBD | |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.2ZN | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.2ZP |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|-------------------+---------------------------|
| Major Release | Availability of Repaired |
| | Releases |
|-------------------+---------------------------|
| Affected | | |
| 12.3-Based | Rebuild | Maintenance |
| Release | | |
|-------------------+-------------+-------------|
| | | 12.3(3h); | |
| | | available | |
| | | 21-Apr-05 | |
| | |-------------| |
| | | 12.3(5e); | |
| | | available | |
| | | 28-Apr-05 | |
| | |-------------| |
| | TCPv4 | 12.3(6e) | |
| |and |-------------|12.3(13) |
| | Tunnels | 12.3(9d); | |
| | | available | |
| | | 21-Apr-05 | |
| | |-------------| |
| | | 12.3(10c) | |
| | |-------------| |
| | | 12.3(12b); | |
| | | available | |
| | | 12-Apr-05 | |
| |---------+-------------+-------------|
| | | 12.3(6e) | |
| | |-------------| |
| | | 12.3(3h); | |
| | | available | |
| | | 21-Apr-05 | |
| | |-------------| |
| | | 12.3(5e); | |
| | TCPv6 | available | 12.3(12) |
| 12.3 | | 28-Apr-05 | |
| | |-------------| |
| | | 12.3(9d); | |
| | | available | |
| | | 21-Apr-05 | |
| | |-------------| |
| | | 12.3(10c) | |
| |---------+-------------+-------------|
| | | 12.3(6e) | |
| | |-------------| |
| | | 12.3(3h); | |
| | | available | |
| | | 21-Apr-05 | |
| | |-------------| |
| | | 12.3(5e); | |
| | | available | |
| | | 28-Apr-05 | |
| | |-------------|12.3(15), |
| | L2TPv2 | 12.3(9d); | available |
| | | available | 6-Jun-05 |
| | | 21-Apr-05 | |
| | |-------------| |
| | | 12.3(12b); | |
| | | available | |
| | | 12-Apr-05 | |
| | |-------------| |
| | | 12.3(13a); | |
| | | available | |
| | | 2-May-05 | |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3B | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | 12.3(9a)BC2 | |
| | Tunnels | | |
|12.3BC |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(7)T8 or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3BW | TCPv6 | Vulnerable; migrate to |
| | | 12.3(7)T8 or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(11)T4 or later |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | | 12.3(4)JA |
| | Tunnels | | |
|12.3JA |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | | 12.3(7)T8 | |
| |TCPv4 |-------------| |
| | and | 12.3(8)T7 | 12.3(14)T |
| |Tunnels |-------------| |
| | | 12.3(11)T4 | |
| |---------+-------------+-------------|
| | | 12.3(7)T8 | |
| | |-------------| |
| 12.3T | TCPv6 | 12.3(8)T7 | 12.3(14)T |
| | |-------------| |
| | | 12.3(11)T4 | |
| |---------+-------------+-------------|
| | | 12.3(11)T4 | |
| | |-------------| |
| | L2TPv2 | 12.3(7)T10; | 12.3(14)T |
| | | available | |
| | | 16-May-05 | |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3XA | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3XB | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | 12.3(2)XC3, | |
| | and | available | |
| | Tunnels | TBD | |
| |---------+-------------+-------------|
| | | 12.3(2)XC3, | |
| 12.3XC | TCPv6 | available | |
| | | TBD | |
| |---------+-------------+-------------|
| | | 12.3(2)XC3, | |
| | L2TPv2 | available | |
| | | TBD | |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3XD | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XE |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3XF | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XG |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; | |
| | and | migrate to | |
| | Tunnels | 12.3(14)T | |
| | | or later | |
| |---------+-------------+-------------|
| | | Vulnerable; | |
| 12.3XH | TCPv6 | migrate to | |
| | | 12.3(14)T | |
| | | or later | |
| |---------+-------------+-------------|
| | | Vulnerable; | |
| | L2TPv2 | migrate to | |
| | | 12.3(14)T | |
| | | or later | |
|---------+---------+-------------+-------------|
| | TCPv4 | 12.3(7)XI3 | |
| |---------+-------------+-------------|
| | | 12.3(7)XI4, | |
| | Tunnels | available | |
| 12.3XI | | TBD | |
| |---------+-------------+-------------|
| | TCPv6 | 12.3(7)XI3 | |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XJ |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XK |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3XL | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(14)T or later |
| | Tunnels | |
| |---------+---------------------------|
| 12.3XM | TCPv6 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; migrate to |
| | | 12.3(14)T or later |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XQ |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XR |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XS |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | Vulnerable; migrate to |
| | and | 12.3(4)JA |
| | Tunnels | |
|12.3XT |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XU |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XW |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3XX |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | 12.3(8)XY4 |
| | Tunnels | |
|12.3XY |---------+---------------------------|
| | TCPv6 | Not vulnerable |
| |---------+---------------------------|
| | L2TPv2 | Not vulnerable |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3YA |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3YD |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | 12.3(11) | |
| | and | YF2, | |
| | Tunnels | available | |
| | | 28-Apr-05 | |
| |---------+-------------+-------------|
| | | 12.3(11) | |
| 12.3YF | TCPv6 | YF2, | |
| | | available | |
| | | 28-Apr-05 | |
| |---------+-------------+-------------|
| | | 12.3(11) | |
| | L2TPv2 | YF2, | |
| | | available | |
| | | 28-Apr-05 | |
|---------+---------+-------------+-------------|
| | TCPv4 | | |
| | and | 12.3(8)YG1 | |
| | Tunnels | | |
|12.3YG |---------+-------------+-------------|
| | TCPv6 | 12.3(8)YG1 | |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3YH |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | | 12.3(8)YI |
| | Tunnels | | |
|12.3YI |---------+-------------+-------------|
| | TCPv6 | | 12.3(8)YI |
| |---------+-------------+-------------|
| | L2TPv2 | | 12.3(8)YI |
|---------+---------+---------------------------|
| | TCPv4 | |
| | and | Vulnerable; contact TAC |
| | Tunnels | |
|12.3YJ |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | | 12.3(11)YK |
| | Tunnels | | |
|12.3YK |---------+-------------+-------------|
| | TCPv6 | | 12.3(11)YK |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | | 12.3(11)YN |
| | Tunnels | | |
|12.3YN |---------+---------------------------|
| | TCPv6 | Vulnerable; contact TAC |
| |---------+---------------------------|
| | L2TPv2 | Vulnerable; contact TAC |
|---------+---------+---------------------------|
| | TCPv4 | | |
| | and | | 12.3(14)YQ |
| | Tunnels | | |
|12.3YQ |---------+-------------+-------------|
| | TCPv6 | | 12.3(14)YQ |
| |---------+-------------+-------------|
| | L2TPv2 | | 12.3(14)YQ |
+-----------------------------------------------+
Non-IOS-based Products
+---------------------
Each row of the non-IOS-based products table (below) lists the earliest
possible release that contains the fix (the "First Fixed Release") and
the anticipated date of availability. A product running a release that
is earlier than the listed release (less than the First Fixed Release)
is known to be vulnerable. The product should be upgraded at least to
the indicated release or a later release (greater than or equal to the
First Fixed Release label).
+-------------------------------------------+
| Product | Bug ID | First Fixed |
| | | Release |
|--------------+------------+---------------|
| | | SMU ID |
| | CSCef45332 | AA01157 for |
| | | IOS XR 3.0.0 |
| IOS XR | | |
| | | SMU ID |
| | | AA01172 for |
| | | IOS XR 3.0.1 |
|--------------+------------+---------------|
| | CSCef46728 | |
| | | |
| 7960 (SCCP) | | 7.1(1) |
| | | |
| | | |
|--------------+------------+---------------|
| | CSCef54947 | |
| | | |
| 7970 (SCCP) | | 6.0(3) |
| | | |
| | | |
|--------------+------------+---------------|
| | CSCef54204 | |
| | | |
| | | |
| | | Release date |
| 7960 (SIP) | | not |
| | | determined |
| | | yet. |
| | | |
| | | |
| | | |
|--------------+------------+---------------|
| | | 6.2.4(101) |
| | | and 6.3.4 |
| | CSCef57566 | (120), both |
| Cisco PIX | | available |
| Security | | from http:// |
| Appliance | | www.cisco.com |
| | | /cgi-bin/ |
| | | tablebuild.pl |
| | | /PIXPSIRT. |
|--------------+------------+---------------|
| | | D00404000018 |
| | | (load 18, DSP |
| | CSCsa60692 | Ver 4.3.25) |
| Catalyst | | for the 6608 |
| 6608 and | | and |
| 6624 | | A00204000010 |
| | | (load 10, DSP |
| | | Ver 4.3.25) |
| | | for the 6624. |
|--------------+------------+---------------|
| Cisco 11000 | CSCeh45454 | Release date |
| and 11500 | | not |
| Content | | determined |
| Services | | yet. |
| Switches | | |
|--------------+------------+---------------|
| | CSCeh20083 | Release date |
| Cisco Global | | not |
| Site | | determined |
| Selector | | yet. |
| | | |
|--------------+------------+---------------|
| Cisco MDS | CSCeh04183 | |
| 9000 Series | | SAN-OS 2.1 |
| Multilayer | | (1a) |
| Switches | | |
| | | |
|--------------+------------+---------------|
| | CSCeh59823 | |
| VPN 5000 | | Please |
| Concentrator | | contact TAC. |
| | | |
| | | |
|--------------+------------+---------------|
| ONS 15454 | See Cisco | |
| IOS-based | bug IDs | R5.0 |
| blades (ML | for Cisco | |
| and SL) | IOS | |
|--------------+------------+---------------|
| ONS 15302 | | |
| and ONS | - | R2.0 |
| 15305 | | |
+-------------------------------------------+
For all Cisco products that are based on a third party Operating System
and when Cisco is not supplying the OS, please contact your respective
vendor for the appropriate patches.
Obtaining Fixed Software
========================
Customers with Service Contracts
+-------------------------------
Customers with contracts should obtain upgraded software through their
regular update channels. For most customers, this means that upgrades
should be obtained through the Software Center on Cisco's worldwide
website at http://www.cisco.com.
Customers using Third-party Support Organizations
+------------------------------------------------
Customers whose Cisco products are provided or maintained through prior
or existing agreement with third-party support organizations such as
Cisco Partners, authorized resellers, or service providers should
contact that support organization for assistance with the upgrade, which
should be free of charge.
Customers without Service Contracts
+----------------------------------
Customers who purchase direct from Cisco but who do not hold a Cisco
service contract and customers who purchase through third-party vendors
but are unsuccessful at obtaining fixed software through their point
of sale should get their upgrades by contacting the Cisco Technical
Assistance Center (TAC). TAC contacts are as follows.
* +1 800 553 2447 (toll free from within North America)
* +1 408 526 7209 (toll call from anywhere in the world)
* e-mail: tac at cisco.com
Please have your product serial number available and give the URL of
this notice as evidence of your entitlement to a free upgrade. Free
upgrades for non-contract customers must be requested through the TAC.
Please do not contact either "psirt at cisco.com" or
"security-alert at cisco.com" for software upgrades.
If you need assistance with the implementation of the workarounds, or
have questions on the workarounds, please contact the Cisco Technical
Assistance Center (TAC).
Customers may only install and expect support for the feature sets they
have purchased. By installing, downloading, accessing, or otherwise
using such software upgrades, customers agree to be bound by the terms
of Cisco's software license terms found at
http://www.cisco.com/public/sw-license-agreement.html,
or as otherwise set forth at Cisco.com Downloads at
http://www.cisco.com/public/sw-center/sw-usingswc.shtml
Workarounds
===========
The effectiveness of any workaround is dependent on specific customer
situations such as product mix, network topology, traffic behavior,
and organizational mission. Due to the variety of affected products
and releases, customers should consult with their service provider
or support organization to ensure any applied workaround is the most
appropriate for use in the intended network before it is deployed.
Effects of Disabling PMTUD
+-------------------------
As will be shown next, one of the most common workarounds to mitigate
the effect of attacks based on crafted ICMP "fragmentation needed and DF
bit set" messages (or ICMPv6 "message too big" messages) is to disable
PMTUD when it is possible to do so through configuration commands.
It is important to note that in general, there should not be negative
side effects to disabling PMTUD. Disabling PMTUD will cause a device
to send its datagrams with the DF bit cleared. When the large packets
reach a small-MTU router, that router will fragment the packets into
multiple smaller ones. The smaller, fragmented data will then reach
the destination, where it will be reassembled into the original large
packet.
Another consideration is that when PMTUD is disabled for TCP, TCP will
not adjust its MSS based on changes in the Path MTU, and the actual MSS
that will be used could cause unnecessary segmentation if its value
is larger than the Path MTU. The MSS value that will be used will be
a manually-set value (through a configuration command) or if nothing
is explicitly configured, a default of 536 bytes if the destination is
remote, or 1460 bytes if the destination is local. To avoid unnecessary
segmentation, it is recommended that the MSS be manually set to a value
small enough to pass through the smallest MTU in the data path.
Finally, please note that in general, disabling PMTUD will have no
effect on existing connections, which means that existing connections
must be manually terminated and re-established.
Voice Applications, PIX Security Appliance and PMTUD
+---------------------------------------------------
Disabling PMTUD on devices that are running voice applications (like
the Cisco CallManager) can create an undesirable condition if the voice
traffic is passing through a Cisco PIX Security Appliance and the PIX
Security Appliance is doing fixups of voice protocols like SCCP (fixup
protocol skinny), SIP (fixup protocol sip) and H.323 (fixup protocol
h323)
Note: the default installation of the Cisco CallManager has PMTUD
disabled.
The problem occurs because the PIX Security Appliance/FWSM software
cannot always fully inspect voice-signaling traffic that has segmented
and/or fragmented protocol data units (PDUs). With PMTUD disabled,
sufficiently large PDUs may be split across multiple TCP segments or IP
fragments, which can cause a failure to properly open the pinholes for
secondary connections and media traffic.
Therefore, when deciding to disable PMTUD on devices running voice
applications, take care to provision the access rules to permit the
necessary secondary signaling and media traffic and to disable the
respective protocol's fixup.
Depending on the local security policy, the requirement of pre-opening
ports may render this workaround of disabling PMTUD inapplicable.
Effects of Filtering Out ICMP Unreachable Messages
+-------------------------------------------------
Another suggested workaround, especially in the case of IPSec and of
those products where it is not possible to disable PMTUD, is to filter
out ICMP "fragmentation needed and DF bit set" messages. It is important
to note that any recommendation to block ICMP "fragmentation needed and
DF bit set" messages applies to messages that are destined to the device
that is being protected, and not for messages destined elsewhere in the
network. Indiscriminately blocking ICMP unreachable messages can lead to
the creation of the "black holes" described in RFC 2923 ("TCP Problems
with Path MTU Discovery" - http://www.ietf.org/rfc/rfc2923.txt).
Additionally, if ICMP "fragmentation needed and DF bit set" messages
are blocked from being received by an end host, the end host must
send packets with the DF bit cleared. This can be accomplished by
disabling PMTUD, or, if there is no way to achieve this, by using
special mechanisms like "crypto ipsec df-bit clear" where supported (in
the case of IPSec).
If ICMP unreachables are being blocked, and packets are sent with the DF
bit set, then the end host will never be able to react to the situation
where an intermediate router needs to fragment packets that are too
big for a certain PMTU; this situation requires either fragmenting the
packet at the source (end host), or re-sending the packet with the DF
bit cleared.
Workarounds for Cisco IOS
+------------------------
* Transmission Control Protocol Over IP Version 4
If PMTUD has been explicitly enabled, a possible workaround to prevent
PMTUD attacks is to disable it by using the global configuration command
no ip tcp path-mtu-discovery. Once this command is executed, PMTUD
will be disabled for all new TCP connections; configuring PMTD on the
IOS device does not have any effect on existing TCP sessions already
established from/to the router.
Please note that with PMTUD disabled, the MSS that will be used will be
the value set with the ip tcp mss command, or the default of 536 bytes
for remote destinations, or 1460 bytes for local destinations.
* Transmission Control Protocol Over IP Version 6
PMTUD is enabled by default when using TCP over IPv6, and it is not
possible to disable it. For this reason a possible workaround is to use
an ACL to block the ICMPv6 "packet too big" message.
Please note that filtering out ICMPv6 "packet too big" messages means
that the layer 3 (IPv6) PMTUD is being shut down as well. Therefore, it
is necessary to make sure that the MTU is set on the end host to the
lowest possible IPv6 MTU - 1280 bytes. Otherwise, since the device is
not seeing the "packet too big" message, the device will not know that
an intermediate system has dropped a packet because it was too big.
ICMPv6 "packet too big" messages are the IPv6 equivalent to the ICMPv4
"fragmentation needed and DF bit set" message. Therefore, the same
considerations presented in the section Effects of Filtering Out ICMP
Unreachable Messages apply to filtering out ICMPv6 "packet too big"
messages.
* IPSec
For IPSec, the recommended workaround is to "disable" PMTUD. Please
note that there is not a single command to disable PMTUD under IPSec,
but this can be achieved through other mechanisms. In particular, the
following two things must be done:
1. Filter out ICMP "fragmentation needed and DF bit set" messages
(type 3, code 4) destined to the router itself using an Access
Control List or the Control Plane Policing (CoPP) feature.
The following example shows how to block ICMP "fragmentation needed
and DF bit set" (type 3, code 4) messages that are addressed to
any of the device's IP addresses using an interface ACL (note how
the type 3, code 4 message is specified using the packet-too-big
keyword):
access-list 111 deny icmp any host <fa0/0's IP address> packet-too-big
access-list 111 deny icmp any host <fa0/1's IP address> packet-too-big
access-list 111 deny icmp any host <fa0/2's IP address> packet-too-big
access-list 111 permit ip any any
!
interface fastEthernet 0/0
ip access-group 111 in
!
interface fastEthernet 0/1
ip access-group 111 in
!
interface fastEthernet 0/2
ip access-group 111 in
Note: for this workaround to be effective, all of the router's IP
addresses must be included in the ACL and the ACL must be applied to
all interfaces.
This type of filtering could be implemented as part of an
Infrastructure ACL, which is a networking best practice.
For more information on iACLs, refer to "Protecting Your
Core: Infrastructure Protection Access Control Lists" at
http://www.cisco.com/warp/public/707/iacl.html.
The following example shows how to use Control Plane Policing to
accomplish the same thing:
access-list 140 permit icmp any host <interface0 IP address> packet-too-big
access-list 140 permit icmp any host <interface1 IP address> packet-too-big
[...]
access-list 140 permit icmp any host <interfaceN IP address> packet-too-big
access-list 140 deny ip any any
!
class-map match-all icmp-class
match access-group 140
!
policy-map control-plane-policy
! Drop all traffic that matches the class "icmp-class"
class icmp-class
drop
!
control-plane
service-policy input control-plane-policy
Note: CoPP is available in IOS release trains 12.0S, 12.2S and
12.3T. Additional information on the configuration and use of the
CoPP feature can be found at the following URL:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1838/products_feature_guide09186a00801afad4.html
2. Allow IPSec to fragment the embedded packet even when the Don't
Fragment bit is set in it. This can be accomplished by using the
command crypto ipsec df-bit clear (which is available in IOS 12.2
(2)T and later) or by using Policy-Based Routing (PBR) (available
in IOS 12.1(6) and later) to clear the DF bit.
What follows is an example of how to use PBR to clear the DF bit:
route-map clear-df permit 10
match ip address 101
!--- The following command is used to change the
!--- Don't Fragment (DF) bit value in the IP header;
!--- it must be used in route-map configuration mode.
set ip df 0
access-list 101 permit tcp 10.1.3.0 0.0.0.255 any
interface ethernet0
...
!--- The following command is used to identify a
!--- route map to use for policy routing on an
!--- interface; if must be used in interface
!--- configuration mode.
ip policy route-map clear-df
In this example the route-map is applied to the interface where
the unencrypted traffic enters the router, and 10.1.3.0/24 is the
address space that is sending traffic through the IPSec tunnel.
* Generic Routing Encapsulation and IPinIP
The only workaround for this case is to disable PMTUD on the tunnel
interface if it has been enabled. This is accomplished via the command
"no tunnel path-mtu-discovery", while in the specific tunnel interface
configuration mode.
Without the "tunnel path-mtu-discovery" command configured, the DF bit
will always be cleared in the GRE IP header. This allows the GRE IP
packet to be fragmented, even though the encapsulated data IP header
had the DF bit set, which normally wouldn't allow the packet to be
fragmented.
* Layer 2 Tunneling Protocol Version 2 and Layer 2 Tunneling Protocol
Version 3
The only workaround to protect Layer 2 Tunneling Protocol sessions
(both versions 2 and 3) against PMTUD attacks is to disable PMTUD if it
has been enabled. For L2TPv2, this is done via the no ip pmtu command
in vpdn-group configuration mode as shown here:
router(config)#vpdn enable
router(config)#vpdn-group 1
router(config-vpdn)#no ip pmtu
For L2TPv3, this is done via the commands no ip pmtu and no ip dfbit
set in pseudowire-class configuration mode as shown here:
pseudowire-class [pseudowire class name]
encapsulation l2tpv3
no ip pmtu
no ip dfbit set
[...]
Workarounds for IOS XR
+---------------------
If a Cisco CRS-1 is establishing TCP sessions with other peers, then
there are no workarounds and customers are recommended to upgrade to a
non-vulnerable version of IOS XR.
Workarounds for Cisco IP Phones
+------------------------------
There are no workarounds for ICMP "hard" error and "source quench"
attacks against Cisco IP Phones. However, these attacks can be
mitigated by segmenting voice and data through the use of VLAN
technologies, and in general, by following recommended best practices
for IP telephony such as those documented in the white paper "SAFE: IP
Telephony Security in Depth" available at
http://www.cisco.com/en/US/netsol/ns340/ns394/ns171/ns128/networking_solutions_white_paper09186a00801b7a50.shtml.
Workarounds for the Cisco PIX Security Appliance
+-----------------------------------------------
As mentioned in the Vulnerable Products section, the PIX Security
Appliance is only affected if IPSec is configured and enabled. If it is
affected, then there are no workarounds (since PMTUD cannot be disabled
on the PIX Security Appliance) and customers are recommended to upgrade
to a non-vulnerable version of the PIX Security Appliance software.
Workarounds for Cisco VPN 5000 Concentrator
+------------------------------------------
It is possible to completely disable PMTUD by setting the configuration
directive PreTunnelFragmentation to "no".
Even if PreTunnelFragmentation is left on with the "yes" setting, it is
worth noting that the VPN 5000 has very strict access rules for incoming
packets. If the attack were to originate from the outside (interface
Ethernet 1), then the packets would always be dropped and have no effect
on the IPSec connection. Packets coming across the tunnel or originating
from the inside interface (Ethernet 0) would still be vulnerable to
PMTUD attacks. Some customers run the device in "single-arm mode," where
only Ethernet 0 is connected and terminates tunnels. Customers under
this scenario are vulnerable.
Workarounds for Other Operating Systems
+--------------------------------------
Cisco has products that run on top of other operating systems, like
Microsoft Windows and different versions of Unix. These products
normally run as end hosts, i.e. not as intermediate systems. Therefore,
they may be affected by the vulnerabilities described in this document
if the operating systems are vulnerable. Some of the workarounds
presented in this section, in particular disabling PMTUD, may also be
valid workarounds for these operating systems.
For information on how to disable Path MTU on Microsoft Windows and
several versions of Unix you can consult the document "Adjusting IP
MTU, TCP MSS, and PMTUD on Windows and Sun Systems" available at
http://cisco.com/en/US/tech/tk870/tk472/tk473/technologies_tech_note09186a008011a218.shtml.
Protecting Against ICMP Source Quench Attacks
+--------------------------------------------
The ICMP "source quench" message was an early attempt at handling
network congestion, but current standards recognize that it is not an
effective method for handling this scenario. For this reason most
modern TCP/IP implementations ignore receipt of such a message and do
not send them. This situation should make it relatively safe to filter
out ICMP "source quench" messages on both vulnerable devices and on the
edge of your network.
Protecting Against Spoofed Packets
+---------------------------------
While considered as Network Best Practices, features like Unicast
Reverse Path Forwarding (uRPF), IP source verify, DHCP Lease Query,
Dynamic ACLs with AAA, and mini-ACLs (also with AAA) that help to
mitigate problems that are caused by spoofed IP source addresses may
be ineffective to mitigate attacks based on ICMP messages when these
ICMP packets are not spoofed. The reason for this is that attackers do
not necessarily need to spoof the source address of their packets to
exploit this vulnerability. However, if an attacker spoofs packets,
implementation of anti-spoofing mechanisms at the edge of the network
will help mitigate the attack.
For more information on anti-spoofing refer to
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml#sec_ip
and RFC 2827 ("Network Ingress Filtering: Defeating Denial of Service
Attacks which employ IP Source Address Spoofing" -
http://www.ietf.org/rfc/rfc2827.txt).
The uRPF feature of IOS helps to mitigate problems that are caused by
spoofed IP source addresses. To enable uRPF, use the following commands:
router(config)# ip cef
router(config)# interface <interface> <interface #>
router(config-if)# ip verify unicast reverse-path
Please consult the feature guide Unicast Reverse Path Forwarding Loose
Mode and ftp://ftp-eng.cisco.com/cons/isp/security/URPF-ISP.pdf for
further details on how uRPF works and how to configure it in various
scenarios. This is especially important if you are using asymmetric
routing.
Exploitation and Public Announcements
=====================================
The Cisco PSIRT is not aware of any malicious use of the
vulnerabilities described in this advisory. NISCC is issuing a public
notice of this industry-wide issue. We would like to thank Fernando
Gont of Argentina's Universidad Tecnologica Nacional/Facultad Regional
Haedo for reporting the ICMP Source Quench and hard error issues to us.
Mr. Gont's full research paper on ICMP blind connection-reset and
throughput-reduction attacks against TCP, including his research on the
PMTU issue can be seen at
http://www.gont.com.ar/drafts/icmp-attacks-against-tcp.html.
Status of This Notice: FINAL
============================
THIS ADVISORY IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY
ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTY OF
MERCHANTABILITY. YOUR USE OF THE INFORMATION ON THE ADVISORY OR
MATERIALS LINKED FROM THE ADVISORY IS AT YOUR OWN RISK. CISCO RESERVES
THE RIGHT TO CHANGE OR UPDATE THIS NOTICE AT ANY TIME.
A stand-alone copy or paraphrase of the text of this security advisory
that omits the distribution URL in the following section is an
uncontrolled copy, and may lack important information or contain factual
errors.
Distribution
============
This advisory will be posted on Cisco's worldwide website at
http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml
In addition to worldwide web posting, a text version of this notice is
clear-signed with the Cisco PSIRT PGP key and is posted to the following
e-mail and Usenet news recipients.
* cust-security-announce at cisco.com
* first-teams at first.org (includes CERT/CC)
* bugtraq at securityfocus.com
* cisco at spot.colorado.edu
* cisco-nsp at puck.nether.net
* full-disclosure at lists.netsys.com
* comp.dcom.sys.cisco at newsgate.cisco.com
Future updates of this advisory, if any, will be placed on Cisco's
worldwide website, but may or may not be actively announced on mailing
lists or newsgroups. Users concerned about this problem are encouraged
to check the above URL for any updates.
Revision History
================
+----------------------------------------+
| Revision | | Initial |
| 1.0 | 2005-April-12 | Public |
| | | Release |
+----------------------------------------+
Cisco Security Procedures
=========================
Complete information on reporting security vulnerabilities in Cisco
products, obtaining assistance with security incidents, and registering
to receive security information from Cisco, is available on Cisco's
worldwide website at
http://www.cisco.com/en/US/products/products_security_vulnerability_policy.html.
This includes instructions for press inquiries regarding Cisco security
notices. All Cisco security advisories are available at
http://www.cisco.com/go/psirt.
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