[c-nsp] Cisco Security Advisory: Multiple DLSw Denial of Service Vulnerabilities in Cisco IOS

Cisco Systems Product Security Incident Response Team psirt at cisco.com
Wed Mar 26 12:00:00 EDT 2008


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Cisco Security Advisory: Multiple DLSw Denial of Service
                         Vulnerabilities in Cisco IOS

Advisory ID: cisco-sa-20080326-dlsw

http://www.cisco.com/warp/public/707/cisco-sa-20080326-dlsw.shtml

Revision 1.0

For Public Release 2008 March 26 1600 UTC (GMT)

Summary
=======

Cisco IOS contains multiple vulnerabilities in the Data-link
Switching (DLSw) feature that may result in a reload or memory leaks
when processing specially crafted UDP or IP Protocol 91 packets.

Cisco has released free software updates that address these
vulnerabilities. Workarounds are available to mitigate the effects of
these vulnerabilities.

This advisory is posted at 
http://www.cisco.com/warp/public/707/cisco-sa-20080326-dlsw.shtml

Note: The March 26, 2008 publication includes five Security
Advisories. The Advisories all affect Cisco's Internetwork Operating
System (IOS). Each Advisory lists the releases that correct the
vulnerability described in the Advisory, and the Advisories also
detail the releases that correct the vulnerabilities in all five
Advisories. Please reference the following software table to find a
release which fixes all published Security Advisories as of March
26th, 2008.

  * March 26th bundled IOS Advisory Table
    http://www.cisco.com/warp/public/707/cisco-sa-20080326-bundle.shtml

Individual publication links are listed below:

  * Cisco IOS Virtual Private Dial-up Network Denial of Service
    Vulnerability
    http://www.cisco.com/warp/public/707/cisco-sa-20080326-pptp.shtml
   
  * Multiple DLSw Denial of Service Vulnerabilities in Cisco IOS
    http://www.cisco.com/warp/public/707/cisco-sa-20080326-dlsw.shtml
   
  * Cisco IOS User Datagram Protocol Delivery Issue For IPv4/IPv6
    Dual-stack Routers
    http://www.cisco.com/warp/public/707/cisco-sa-20080326-IPv4IPv6.shtml
   
  * Vulnerability in Cisco IOS with OSPF, MPLS VPN, and Supervisor
    32, Supervisor 720, or Route Switch Processor 720
    http://www.cisco.com/warp/public/707/cisco-sa-20080326-queue.shtml
   
  * Cisco IOS Multicast Virtual Private Network (MVPN) Data Leak
    http://www.cisco.com/warp/public/707/cisco-sa-20080326-mvpn.shtml

Affected Products
=================

Vulnerable Products
+------------------

This security advisory applies to all Cisco products that run any
version of affected Cisco IOS software configured for DLSw. Systems
that contain the DLSw feature, but do not have it enabled, are not
affected.

Routers enabled for DLSw contain a line in the configuration defining
a local DLSw peer. This configuration can be observed by issuing the
command "show running-config". Systems configured for DLSw contain
lines similar to the following:

    "dlsw local-peer"

or

    "dlsw local-peer peer-id <IP address>"

Any version of Cisco IOS prior to the versions which are listed in
the Software Versions and Fixes section below is vulnerable.

To determine the version of Cisco IOS 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". On the next
line of output, the image name will be displayed between parentheses,
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 Cisco IOS
Software Release 12.3(6) with an installed image name of C3640-IS-M:

    Cisco Internetwork Operating System Software
    IOS (tm) 3600 Software (C3640-IS-M), Version 12.3(6), RELEASE SOFTWARE (fc3)

The next example shows a product running Cisco IOS Software Release
12.3(11)T3 with an image name of C3845-ADVIPSERVICESK9-M:

    Cisco IOS Software, 3800 Software (C3845-ADVIPSERVICESK9-M), Version 12.3(11)T3, RELEASE SOFTWARE (fc4)
    Technical Support: http://www.cisco.com/techsupport
    Copyright (c) 1986-2005 by Cisco Systems, Inc.

Additional information about Cisco IOS release naming can be found at
http://www.cisco.com/warp/public/620/1.html.

Products Confirmed Not Vulnerable
+--------------------------------

Cisco IOS devices that are not configured for DLSw are not
vulnerable.

No other Cisco products are currently known to be affected by these
vulnerabilities.

Details
=======

Data-link switching (DLSw) provides a means of transporting IBM
Systems Network Architecture (SNA) and network basic input/output
system (NetBIOS) traffic over an IP network. Cisco implementation of
DLSw also uses UDP port 2067 and IP Protocol 91 for Fast Sequenced
Transport (FST).

Multiple vulnerabilities exists in Cisco IOS when processing UDP and
IP protocol 91 packets. These vulnerabilities do not affect TCP
packet processing. A successful exploitation may result in a reload
of the system or a memory leak on the device, leading to a denial of
service (DoS) condition.

Cisco IOS devices configured for DLSw with "dlsw local-peer"
automatically listen for IP protocol 91 packets. A Cisco IOS device
that is configured for DLSw with the "dlsw local-peer peer-id
<IP-address>" command listen for IP protocol 91 packets and UDP port
2067.

Cisco IOS devices listen to IP protocol 91 packets when DLSw is
configured. However, it is only used if DLSw is configured for Fast
Sequenced Transport (FST). A DLSw FST peer configuration will contain
the following line:

    "dlsw remote-peer 0 fst <ip-address>"

It is possible to disable UDP processing in DLSw with the "dlsw
udp-disable" command. However, disabling UDP only prevents the 
sending of UDP packets, it does not prevent the device from receiving
and processing incoming UDP packets.

These vulnerabilities are documented in Cisco Bug ID CSCsk73104 
and have been assigned Common Vulnerabilities and Exposures (CVE) ID
CVE-2008-1152.

Vulnerability Scoring Details
=============================

Cisco has provided scores for the vulnerabilities in this advisory
based on the Common Vulnerability Scoring System (CVSS). The CVSS
scoring in this Security Advisory is done in accordance with CVSS
version 2.0.

CVSS is a standards-based scoring method that conveys vulnerability
severity and helps determine urgency and priority of response.

Cisco has provided a base and temporal score. Customers can then
compute environmental scores to assist in determining the impact of
the vulnerability in individual networks.

Cisco has provided an FAQ to answer additional questions regarding
CVSS at
http://www.cisco.com/web/about/security/intelligence/cvss-qandas.html

Cisco has also provided a CVSS calculator to help compute the
environmental impact for individual networks at
http://intellishield.cisco.com/security/alertmanager/cvss 

CSCsk73104 - Handling of malformed packets by DLSW

  CVSS Base Score - 7.8

  Access Vector:          Network
  Access Complexity:      Low
  Authentication:         None

  Confidentiality Impact: None
  Integrity Impact:       None
  Availability Impact:    Complete

  CVSS Temporal Score - 6.4

  Exploitability:         Functional
  Remediation Level:      Official-Fix
  Report Confidence:      Confirmed

Impact
======

Successful exploitation of these vulnerabilities may result in the
reload of the device or memory leaks, leading to a DoS condition.

Software Versions and Fixes
===========================

When considering software upgrades, also consult 
http://www.cisco.com/go/psirt 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) or your contracted
maintenance provider for assistance.

Each row of the Cisco IOS software table (below) names a Cisco IOS
release train. If a given release train is vulnerable, then the
earliest possible releases that contain the fix (along with the
anticipated date of availability for each, if applicable) are listed
in the "First Fixed Release" column of the table. The "Recommended
Release" column indicates the releases which have fixes for all the
published vulnerabilities at the time of this Advisory. 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. Cisco recommends upgrading to a release equal to or
later than the release in the "Recommended Releases" column of the
table.

+----------------------------------------+
|   Major    | Availability of Repaired  |
|  Release   |         Releases          |
|------------+---------------------------|
|  Affected  | First Fixed | Recommended |
| 12.0-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0       | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(8)DA3  |             |
|            | are         |             |
|            | vulnerable, |             |
|            | release     |             |
| 12.0DA     | 12.0(8)DA3  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | migrate to  |             |
|            | any release |             |
|            | in 12.2DA   |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(7)DB   |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.0DB     | release     | 12.4(18a)   |
|            | 12.0(7)DB   |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(7)DC   |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.0DC     | release     | 12.4(18a)   |
|            | 12.0(7)DC   |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(17)S5  |             |
|            | are         |             |
| 12.0S      | vulnerable, | 12.0(32)S10 |
|            | release     |             |
|            | 12.0(17)S5  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|------------+-------------+-------------|
| 12.0SC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SP     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0ST     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0T      | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.0W      | Vulnerable; | 12.0(3c)W5  |
|            | contact TAC | (8)         |
|------------+-------------+-------------|
| 12.0WC     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.0WT     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XA     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.0XB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(2)XC2  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.0XC     | release     | 12.3(26)    |
|            | 12.0(2)XC2  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XD     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XE     | first fixed |             |
|            | in 12.1E    |             |
|------------+-------------+-------------|
| 12.0XF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XG     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XH     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(4)XI2  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.0XI     | release     | 12.3(26)    |
|            | 12.0(4)XI2  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.0(4)XJ5  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.0XJ     | release     | 12.3(26)    |
|            | 12.0(4)XJ5  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XK     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.0XL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XM     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XN     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XQ     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0XR     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.0XS     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XV     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.1-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1       | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1AA     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1AX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(22)AY1 |             |
|            | are         |             |
| 12.1AY     | vulnerable, | 12.1(22)    |
|            | release     | EA11        |
|            | 12.1(22)AY1 |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|------------+-------------+-------------|
| 12.1AZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1CX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1DA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(4)DB1  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.1DB     | release     | 12.4(18a)   |
|            | 12.1(4)DB1  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(4)DC2  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.1DC     | release     | 12.4(18a)   |
|            | 12.1(4)DC2  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.1E      | 12.1(27b)E4 |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(11)EA1 |             |
|            | are         |             |
| 12.1EA     | vulnerable, | 12.1(22)    |
|            | release     | EA11        |
|            | 12.1(11)EA1 |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|------------+-------------+-------------|
| 12.1EB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1EC     | migrate to  | 12.3(23)BC1 |
|            | any release |             |
|            | in 12.2BC   |             |
|------------+-------------+-------------|
| 12.1EO     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1EU     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1EV     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1EW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1EX     | first fixed |             |
|            | in 12.1E    |             |
|------------+-------------+-------------|
| 12.1EY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1EZ     | first fixed |             |
|            | in 12.1E    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1GA     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1GB     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1T      | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XA     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1XB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XC     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XD     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1XE     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1XF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XG     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XH     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XI     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XJ     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1XK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1XL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XM     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1XN     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1XO     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XP     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XQ     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1XR     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XS     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(3)XT2  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.1XT     | release     | 12.3(26)    |
|            | 12.1(3)XT2  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1XU     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(5)XV1  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.1XV     | release     | 12.3(26)    |
|            | 12.1(5)XV1  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XW     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XX     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XY     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1XZ     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1YA     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1YB     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1YC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1YD     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.1(5)YE1  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.1YE     | release     | 12.3(26)    |
|            | 12.1(5)YE1  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1YF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1YG     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.1YH     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.1YI     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.1YJ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.2-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2       | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2B      | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2BC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2BW     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2BY     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2BZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2CX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2CY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2CZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2DA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2DD     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2DX     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2EU     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2EW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2EWA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2EX     | migrate to  | 12.2(40)EX1 |
|            | any release |             |
|            | in 12.2SEA  |             |
|------------+-------------+-------------|
| 12.2EY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2EZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2FX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2FY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2FZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2IXA    | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.2IXB    | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.2IXC    | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.2IXD    | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
|            | migrate to  | IXF;        |
| 12.2IXE    | any release | Available   |
|            | in 12.2IXF  | on          |
|            |             | 31-MAR-08   |
|------------+-------------+-------------|
| 12.2JA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2JK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2MB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2MC     | 12.2(15)    | 12.4(18a)   |
|            | MC2h        |             |
|------------+-------------+-------------|
| 12.2S      | 12.2(25)S15 | 12.2(25)S15 |
|------------+-------------+-------------|
|            | 12.2(28)    |             |
|            | SB10        |             |
|            |             |             |
|            | 12.2(31)SB9 | 12.2(28)    |
| 12.2SB     |             | SB12        |
|            | 12.2(33)SB; |             |
|            | Available   |             |
|            | on          |             |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
|            | first fixed |             |
|            | in 12.2SB   |             |
|            |             |             |
| 12.2SBC    | Vulnerable; | 12.2(28)    |
|            | first fixed | SB12        |
|            | in 12.2SB;  |             |
|            | Available   |             |
|            | on          |             |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
| 12.2SCA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SE     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEB    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SED    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEE    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEF    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEG    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SG     | 12.2(44)SG  | 12.2(44)SG  |
|------------+-------------+-------------|
| 12.2SGA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SM     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SO     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SRA    | 12.2(33)    | 12.2(33)    |
|            | SRA6        | SRA7        |
|------------+-------------+-------------|
|            | 12.2(33)    | 12.2(33)    |
|            | SRB3;       | SRB3;       |
| 12.2SRB    | Available   | Available   |
|            | on          | on          |
|            | 31-MAR-08   | 31-MAR-08   |
|------------+-------------+-------------|
| 12.2SRC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SU     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.2(29a)   |             |
|            | SV1 are     |             |
|            | vulnerable, |             |
|            | release     |             |
| 12.2SV     | 12.2(29a)   | 12.2(29b)SV |
|            | SV1 and     |             |
|            | later are   |             |
|            | not         |             |
|            | vulnerable; |             |
|            | migrate to  |             |
|            | any release |             |
|            | in 12.2SVA  |             |
|------------+-------------+-------------|
| 12.2SVA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SVC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SVD    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.2(25)    |             |
|            | SW10 are    |             |
|            | vulnerable, |             |
| 12.2SW     | release     |             |
|            | 12.2(25)    |             |
|            | SW10 and    |             |
|            | later are   |             |
|            | not         |             |
|            | vulnerable; |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2SX     | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2SXA    | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2SXB    | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2SXD    | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2SXE    | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            | 12.2(18)    |             |
|            | SXF12       |             |
|            |             |             |
| 12.2SXF    | 12.2(18)    | 12.2(18)    |
|            | SXF12a      | SXF13       |
|            |             |             |
|            | 12.2(18)    |             |
|            | SXF13a      |             |
|------------+-------------+-------------|
| 12.2SXH    | 12.2(33)    |             |
|            | SXH1        |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2SY     | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            |             | 12.2(25)S15 |
|            | Vulnerable; |             |
| 12.2SZ     | first fixed | 12.2(28)    |
|            | in 12.2S    | SB12        |
|            |             |             |
|            |             | 12.2(33)SRC |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2T      | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2TPC    | 12.2(8)     |             |
|            | TPC10d      |             |
|------------+-------------+-------------|
| 12.2UZ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XA     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XB     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XC     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XD     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2XE     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XG     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XH     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2XI     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XJ     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XK     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XL     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XM     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2XN     | 12.2(33)XN1 | 12.3(26)    |
|------------+-------------+-------------|
| 12.2XO     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XQ     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2XR     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XS     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XT     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XU     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XV     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2XW     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.2(4)YA8  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.2YA     | release     | 12.3(26)    |
|            | 12.2(4)YA8  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YB     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YC     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YD     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            |             | 12.2(25)S15 |
|            | Vulnerable; |             |
| 12.2YE     | first fixed | 12.2(28)    |
|            | in 12.2S    | SB12        |
|            |             |             |
|            |             | 12.2(33)SRC |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YF     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2YG     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YH     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.2(8)YJ1  |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.2YJ     | release     | 12.3(26)    |
|            | 12.2(8)YJ1  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.3     |             |
|------------+-------------+-------------|
| 12.2YK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YL     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YM     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YN     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2YO     | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
| 12.2YP     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YQ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YR     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YS     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YT     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YU     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.2(11)YV1 |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.2YV     | release     | 12.4(18a)   |
|            | 12.2(11)YV1 |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YW     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YX     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YY     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            |             | 12.2(25)S15 |
|            | Vulnerable; |             |
| 12.2YZ     | first fixed | 12.2(28)    |
|            | in 12.2S    | SB12        |
|            |             |             |
|            |             | 12.2(33)SRC |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(18)    |
| 12.2ZA     | first fixed | SXF13       |
|            | in 12.2SXF  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZB     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2ZC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2ZD     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZE     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZF     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2ZG     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.2(13)ZH6 |             |
|            | are         |             |
|            | vulnerable, |             |
| 12.2ZH     | release     | 12.2(13)    |
|            | 12.2(13)ZH6 | ZH11        |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|            | first fixed |             |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZJ     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.4(15)T4  |
| 12.2ZL     | first fixed |             |
|            | in 12.4     | 12.4(18a)   |
|------------+-------------+-------------|
| 12.2ZP     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.2(33)    |
| 12.2ZU     | first fixed | SXH2        |
|            | in 12.2SXH  |             |
|------------+-------------+-------------|
| 12.2ZY     | 12.2(18)ZY2 | 12.2(18)ZY2 |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.3-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
| 12.3       | 12.3(24)    | 12.3(26)    |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3B      | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.3BC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3BW     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.3EU     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3JA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3JEA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3JEB    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3JEC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Releases    |             |
|            | prior to    |             |
|            | 12.3(8)JK1  |             |
|            | are         |             |
| 12.3JK     | vulnerable, | 12.3(8)JK1  |
|            | release     |             |
|            | 12.3(8)JK1  |             |
|            | and later   |             |
|            | are not     |             |
|            | vulnerable; |             |
|------------+-------------+-------------|
| 12.3JL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3JX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3T      | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.3TPC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3VA     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
|            | 12.3(2)XA7; | 12.3(2)XA7; |
| 12.3XA     | Available   | Available   |
|            | on          | on          |
|            | 31-MAR-08   | 31-MAR-08   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XB     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            |             | 12.4(15)T4  |
| 12.3XC     | 12.3(2)XC5  |             |
|            |             | 12.4(18a)   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XD     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | 12.3(2)XE6; | 12.4(15)T4  |
| 12.3XE     | Available   |             |
|            | on          | 12.4(18a)   |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XF     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
|            | first fixed | 12.4(15)T4  |
| 12.3XG     | in 12.3YG;  |             |
|            | Available   | 12.4(18a)   |
|            | on          |             |
|            | 16-JUN-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XH     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | 12.3(7)     |             |
|            | XI11;       |             |
| 12.3XI     | Available   |             |
|            | on          |             |
|            | 18-SEP-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.3(14)    |
| 12.3XJ     | first fixed | YX11        |
|            | in 12.3YX   |             |
|            |             | 12.4(15)T4  |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XK     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XQ     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | 12.3(7)XR8; | 12.3(7)XR8; |
| 12.3XR     | Available   | Available   |
|            | on          | on          |
|            | 31-MAR-08   | 31-MAR-08   |
|------------+-------------+-------------|
| 12.3XS     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XU     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.3(14)    |
| 12.3XW     | first fixed | YX11        |
|            | in 12.3YX   |             |
|            |             | 12.4(15)T4  |
|------------+-------------+-------------|
| 12.3XY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3YA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.3YD     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.3(14)    |
| 12.3YF     | first fixed | YX11        |
|            | in 12.3YX   |             |
|            |             | 12.4(15)T4  |
|------------+-------------+-------------|
|            | 12.3(8)YG7; |             |
| 12.3YG     | Available   | 12.4(15)T4  |
|            | on          |             |
|            | 16-JUN-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YH     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YI     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YJ     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YK     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.3YM     | 12.3(14)    | 12.3(14)    |
|            | YM12        | YM12        |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YQ     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | 12.3(11)    |             |
|            | YS3;        |             |
| 12.3YS     | Available   | 12.4(15)T4  |
|            | on          |             |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YT     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YU     | first fixed |             |
|            | in 12.4XB   |             |
|------------+-------------+-------------|
| 12.3YX     | 12.3(14)    | 12.3(14)    |
|            | YX11        | YX11        |
|------------+-------------+-------------|
| 12.3YZ     | 12.3(11)YZ3 |             |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.4-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
|            | 12.4(10c)   |             |
|            |             |             |
|            | 12.4(13e)   |             |
|            |             |             |
|            | 12.4(16b)   |             |
| 12.4       |             | 12.4(18a)   |
|            | 12.4(17)    |             |
|            |             |             |
|            | 12.4(3h)    |             |
|            |             |             |
|            | 12.4(8d)    |             |
|------------+-------------+-------------|
| 12.4JA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4JK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4JMA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4JMB    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4JMC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4JX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | 12.4(15)MD; |             |
| 12.4MD     | Available   |             |
|            | on          |             |
|            | 09-MAY-08   |             |
|------------+-------------+-------------|
| 12.4MR     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4SW     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
|            | 12.4(15)T2  |             |
|            |             |             |
| 12.4T      | 12.4(6)T10  | 12.4(15)T4  |
|            |             |             |
|            | 12.4(9)T7   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.4XA     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.4XB     | 12.4(2)XB6  |             |
|------------+-------------+-------------|
| 12.4XC     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.4XD     | 12.4(4)XD10 | 12.4(4)XD10 |
|------------+-------------+-------------|
| 12.4XE     | 12.4(6)XE2  | 12.4(15)T4  |
|------------+-------------+-------------|
| 12.4XF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XG     | 12.4(9)XG2  | 12.4(9)XG2  |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.4XJ     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.4XK     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.4XL     | 12.4(15)XL2 |             |
|------------+-------------+-------------|
| 12.4XM     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XN     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XT     | 12.4(6)XT2  | 12.4(6)XT2  |
|------------+-------------+-------------|
| 12.4XV     | 12.4(11)XV  |             |
|------------+-------------+-------------|
| 12.4XW     | Vulnerable; | 12.4(11)XW6 |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.4XY     | Not         |             |
|            | Vulnerable  |             |
+----------------------------------------+

A special patch for Cisco IOS Software Modularity is also available
and can be downloaded from the Cisco IOS Software Modularity Patch
Navigator at http://tools.cisco.com/swdf/ionpn/jsp/main.jsp.

Workarounds
===========

The workaround consists of filtering UDP packets to port 2067 and IP
protocol 91 packets. Filters can be applied at network boundaries to
filter all IP protocol 91 packets and UDP packets to port 2067 or can
be applied on individual affected devices to permit such traffic only
from trusted peer IP addresses. However, since both of the protocols
are connectionless, it is possible for an attacker to spoof malformed
packets from legitimate peer IP addresses.

As soon as DLSw is configured, the Cisco IOS device begins listening
on IP protocol 91. However, this protocol is only used if DLSw is
configured for Fast Sequenced Transport (FST). A DLSw FST peer
configuration will contain the following line:

    "dlsw remote-peer 0 fst <ip-address>"

If FST is used, filtering IP protocol 91 will break the operation, so
filters need to permit protocol 91 traffic from legitimate peer IP
addresses.

It is possible to disable UDP processing in DLSw with the "dlsw
udp-disable" command. However, disabling UDP only prevents the sending
of UDP packets, it does not prevent the receiving and processing of
incoming UDP packets. To protect a vulnerable device from malicious
packets via UDP port 2067, both of the following actions must be
taken:

 1. Disable UDP outgoing packets with the "dlsw udp-disable" command,
    AND
 2. Filter UDP 2067 in the vulnerable device using infrastructure
    ACL.

Additional mitigation techniques that can be deployed on Cisco
devices within the network are available in the Cisco Applied
Mitigation Bulletin companion document for this advisory:

http://www.cisco.com/warp/public/707/cisco-amb-20080326-dlsw.shtml

Using Control Plane Policing on Affected Devices
+-----------------------------------------------

Control Plane Policing (CoPP) can be used to block untrusted DLSw
traffic to the device. Cisco IOS software releases 12.0S, 12.2SX,
12.2S, 12.3T, 12.4, and 12.4T support the CoPP feature. CoPP may be
configured on a device to protect the management and control planes
to minimize the risk and effectiveness of direct infrastructure
attacks by explicitly permitting only authorized traffic sent to
infrastructure devices in accordance with existing security policies
and configurations. The following example, which uses 192.168.100.1
to represent a trusted host, can be adapted to your network. If FST
is not used, protocol 91 may be completely filtered. Additionally, if
UDP is disabled with the "dlsw udp-disable" command, UDP port 2067 
may also be completely filtered.

    
    !--- Deny DLSw traffic from trusted hosts to all IP addresses
    !--- configured on all interfaces of the affected device so that
    !--- it will be allowed by the CoPP feature
    
    access-list 111 deny udp host 192.168.100.1 any eq 2067
    access-list 111 deny 91 host 192.168.100.1 any
    
    !--- Permit all other DLSw traffic sent to all IP addresses
    !--- configured on all interfaces of the affected device so that it
    !--- will be policed and dropped by the CoPP feature
    
    access-list 111 permit udp any any eq 2067
    access-list 111 permit 91 any any 
    
    !--- Permit (Police or Drop)/Deny (Allow) all other Layer 3 and Layer 4
    !--- traffic in accordance with existing security policies and
    !--- configurations for traffic that is authorized to be sent
    !--- to infrastructure devices
    !--- Create a Class-Map for traffic to be policed by
    !--- the CoPP feature
    
    class-map match-all drop-DLSw-class
     match access-group 111
    
    !--- Create a Policy-Map that will be applied to the
    !--- Control-Plane of the device.
    
    policy-map drop-DLSw-traffic
     class drop-DLSw-class
      drop
    
    !--- Apply the Policy-Map to the Control-Plane of the
    !--- device
    
    control-plane
     service-policy input drop-DLSw-traffic

In the above CoPP example, the access control entries (ACEs) which
match the potential exploit packets with the "permit" action result
in these packets being discarded by the policy-map "drop" function,
while packets that match the "deny" action (not shown) are not
affected by the policy-map drop function. Please note that in the
Cisco IOS 12.2S and 12.0S trains the policy-map syntax is different:

    policy-map drop-DLSw-traffic
     class drop-DLSw-class
      police 32000 1500 1500 conform-action drop exceed-action drop

Additional information on the configuration and use of the CoPP
feature is available at 
http://www.cisco.com/en/US/products/ps6642/products_white_paper0900aecd804fa16a.shtml 
and http://www.cisco.com/en/US/products/sw/iosswrel/ps1838/products_feature_guide09186a008052446b.html.

Using Infrastructure ACLs at Network Boundary
+--------------------------------------------

Although it is often difficult to block traffic transiting your
network, it is possible to identify traffic that should never be
allowed to target your infrastructure devices and block that traffic
at the border of your network. iACLs are a network security best
practice and should be considered as a long-term addition to good
network security as well as a workaround for this specific
vulnerability. The iACL example shown below should be included as
part of the deployed infrastructure access-list that will protect all
devices with IP addresses in the infrastructure IP address range. If
FST is not used, protocol 91 may be completely filtered.
Additionally, if UDP is disabled with the "dlsw udp-disable" command,
UDP port 2067 may also be completely filtered.

    
    !--- Permit DLSw (UDP port 2067 and IP protocol 91) packets
    !--- from trusted hosts destined to infrastructure addresses.
    
    access-list 150 permit udp TRUSTED_HOSTS MASK INFRASTRUCTURE_ADDRESSES MASK eq 2067
    access-list 150 permit 91 TRUSTED_HOSTS MASK INFRASTRUCTURE_ADDRESSES MASK 
    
    !--- Deny DLSw (UDP port 2067 and IP protocol 91) packets from 
    !--- all other sources destined to infrastructure addresses.
    
    access-list 150 deny udp any INFRASTRUCTURE_ADDRESSES MASK eq 2067
    access-list 150 deny 91 any INFRASTRUCTURE_ADDRESSES MASK
    
    !--- Permit/deny all other Layer 3 and Layer 4 traffic in accordance
    !--- with existing security policies and configurations
    !--- Permit all other traffic to transit the device.
    
    access-list 150 permit ip any any
    interface serial 2/0
     ip access-group 150 in

The white paper entitled "Protecting Your Core: Infrastructure
Protection Access Control Lists" presents guidelines and recommended
deployment techniques for infrastructure protection access lists.
This white paper can be obtained at the following link:

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_white_paper09186a00801a1a55.shtml

Obtaining Fixed Software
========================

Cisco has released free software updates that address these
vulnerabilities. Prior to deploying software, customers should
consult their maintenance provider or check the software for feature
set compatibility and known issues specific to their environment.

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/en/US/products/prod_warranties_item09186a008088e31f.html
or as otherwise set forth at Cisco.com Downloads at 
http://www.cisco.com/public/sw-center/sw-usingswc.shtml.

Do not contact psirt at cisco.com or security-alert at cisco.com for
software upgrades.

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 agreements with third-party support organizations,
such as Cisco Partners, authorized resellers, or service providers
should contact that support organization for guidance and assistance
with the appropriate course of action in regards to this advisory.

The effectiveness of any workaround or fix 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 or
fix is the most appropriate for use in the intended network before it
is deployed.

Customers without Service Contracts
+----------------------------------

Customers who purchase direct from Cisco but do not hold a Cisco
service contract, and customers who purchase through third-party
vendors but are unsuccessful in obtaining fixed software through
their point of sale should acquire 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

Customers should have their product serial number available and be
prepared to give the URL of this notice as evidence of entitlement to
a free upgrade. Free upgrades for non-contract customers must be
requested through the TAC.

Refer to http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml
for additional TAC contact information, including localized telephone
numbers, and instructions and e-mail addresses for use in various
languages.

Exploitation and Public Announcements
=====================================

The Cisco PSIRT is not aware of any public announcements or malicious
use of the vulnerability described in this advisory.

These vulnerabilities were found internally.

Status of this Notice: FINAL
============================

THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY
KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE
INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS
AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS
DOCUMENT AT ANY TIME.

A stand-alone copy or Paraphrase of the text of this document 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 is posted on Cisco's worldwide website at :

http://www.cisco.com/warp/public/707/cisco-sa-20080326-dlsw.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
  * bugtraq at securityfocus.com
  * vulnwatch at vulnwatch.org
  * cisco at spot.colorado.edu
  * cisco-nsp at puck.nether.net
  * full-disclosure at lists.grok.org.uk
  * 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      | 2008-Mar-26 | 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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