[c-nsp] Cisco Security Advisory: Cisco IOS Multicast Virtual Private Network (MVPN) Data Leak

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: Cisco IOS Multicast Virtual Private Network
                         (MVPN) Data Leak

Advisory ID: cisco-sa-20080326-mvpn

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

Revision 1.0

For Public Release 2008 March 26 1600 UTC (GMT)

Summary
=======

A vulnerability in the Cisco implementation of Multicast Virtual
Private Network (MVPN) is subject to exploitation that can allow a
malicious user to create extra multicast states on the core routers
or receive multicast traffic from other Multiprotocol Label Switching
(MPLS) based Virtual Private Networks (VPN) by sending specially
crafted messages.

Cisco has released free software updates that address this
vulnerability. Workarounds that mitigate this vulnerability are
available.

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

Note: The March 26, 2008 publication includes five Security
Advisories. The Advisories all affect Cisco 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 that 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
+------------------

Devices that run Cisco IOS and are configured for MVPN are affected.

An IOS device that is configured for MVPN has a line that is similar
to this in the running configuration example:

    mdt default <group-address>

In order to determine the software that runs on a Cisco IOS product,
log in to the device and issue the show version command to display
the system banner. Cisco IOS® software identifies itself as
"Internetwork Operating System Software" or simply "IOS." On the next
line of output, the image name displays between parentheses, followed
by "Version" and the Cisco IOS release name. Other Cisco devices do
not have the "show version" command or give different output.

The following example shows output from a device that runs an IOS
image:

    Router>show version
        Cisco IOS Software, 7200 Software (C7200-IK9S-M), Version 12.3(14)T1, RELEASE SOFTWARE (fc1)
        Technical Support: http://www.cisco.com/techsupport
        Copyright (c) 1986-2005 by Cisco Systems, Inc.
        Compiled Thu 31-Mar-05 08:04 by yiyan

Additional information about Cisco IOS release naming is available at
the following link: 
http://www.cisco.com/en/US/products/sw/iosswrel/ps1828/products_white_paper09186a008018305e.shtml.

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

No other Cisco products, including IOS XR software, are currently
known to be affected by this vulnerability.

Details
=======

MVPN architecture introduces an additional set of protocols and
procedures that help enable a service provider to support multicast
traffic in an MPLS VPN. MVPN allows the transparent transport of IP
multicast traffic across the MPLS VPN backbone of a provider and
allows a service provider to offer multicast services to MPLS VPN
customers.

A vulnerability exists in the implementation of MVPN that allows an
attacker to send specially crafted Multicast Distribution Tree (MDT)
Data Join messages that can cause the creation of extra multicast
states on the core routers. MDT Data Join messages can be sent in
unicast or multicast. The vulnerability can also allow leaking
multicast traffic from different MPLS VPNs. It is possible to receive
multicast traffic from VPNs that are not connected to the same
Provider Edge (PE) router. In order to successfully exploit this
vulnerability, an attacker needs to know or guess the Border Gateway
Protocol (BGP) peering IP address of a remote PE router and the
address of the multicast group that is used in other MPLS VPNs.

This vulnerability is documented in the Cisco Bug ID CSCsi01470 
and has been assigned Common Vulnerabilities and Exposures (CVE) ID 
CVE-2008-1156.

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 

CSCsi01470 - Crafted MDT Data Join TLV in VRF causes multicast state

  CVSS Base Score - 7.5

  Access Vector:          Network
  Access Complexity:      Low
  Authentication:         None

  Confidentiality Impact: Partial
  Integrity Impact:       Partial
  Availability Impact:    Partial

  CVSS Temporal Score - 6.2

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

Impact
======

Successful exploitation of the vulnerability can result in the
creation of extra multicast states on the core routers or the leaking
of multicast traffic from one MPLS VPN to another.

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  |             |             |
|------------+-------------+-------------|
| 12.0       | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0DA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0DB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0DC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | 12.0(32)S9  |             |
| 12.0S      |             | 12.0(32)S10 |
|            | 12.0(33)S   |             |
|------------+-------------+-------------|
| 12.0SC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0SP     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0ST     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.0SX     | first fixed | 12.0(32)S10 |
|            | in 12.0S    |             |
|------------+-------------+-------------|
| 12.0SY     | 12.0(32)SY4 | 12.0(32)SY5 |
|------------+-------------+-------------|
| 12.0SZ     | 12.0(30)SZ4 | 12.0(32)S10 |
|------------+-------------+-------------|
| 12.0T      | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0W      | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0WC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0WT     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XD     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XE     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XG     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XH     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XI     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XJ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XM     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XN     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XQ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XR     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XS     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XV     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.0XW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.1-Based |   Release   |   Release   |
|  Releases  |             |             |
|----------------------------------------|
|    There are no affected 12.1 based    |
|                releases                |
|----------------------------------------|
|  Affected  | First Fixed | Recommended |
| 12.2-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
| 12.2       | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2B      | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2BC     | first fixed | 12.3(23)BC1 |
|            | in 12.3BC   |             |
|------------+-------------+-------------|
| 12.2BW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2BY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2BZ     | first fixed |             |
|            | in 12.3XI   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2CX     | first fixed | 12.3(23)BC1 |
|            | in 12.3BC   |             |
|------------+-------------+-------------|
| 12.2CY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2CZ     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
| 12.2DA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2DD     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2DX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            |             | 12.2(25)    |
|            |             | EWA13       |
|            | Vulnerable; |             |
| 12.2EU     | first fixed | 12.2(31)    |
|            | in 12.2SG   | SGA5        |
|            |             |             |
|            |             | 12.2(44)SG  |
|------------+-------------+-------------|
|            |             | 12.2(25)    |
|            |             | EWA13       |
|            | Vulnerable; |             |
| 12.2EW     | first fixed | 12.2(31)    |
|            | in 12.2SG   | SGA5        |
|            |             |             |
|            |             | 12.2(44)SG  |
|------------+-------------+-------------|
|            | 12.2(25)    |             |
|            | EWA10       | 12.2(25)    |
| 12.2EWA    |             | EWA13       |
|            | 12.2(25)    |             |
|            | EWA11       |             |
|------------+-------------+-------------|
| 12.2EX     | 12.2(37)EX  | 12.2(40)EX1 |
|------------+-------------+-------------|
| 12.2EY     | 12.2(37)EY  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2EZ     | first fixed |             |
|            | in 12.2SEE  |             |
|------------+-------------+-------------|
| 12.2FX     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2FY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2FZ     | first fixed | 12.2(44)SE1 |
|            | in 12.2SE   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2IXA    | first fixed |             |
|            | in 12.2IXD  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2IXB    | first fixed |             |
|            | in 12.2IXD  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2IXC    | first fixed |             |
|            | in 12.2IXD  |             |
|------------+-------------+-------------|
| 12.2IXD    | 12.2(18)    |             |
|            | IXD1        |             |
|------------+-------------+-------------|
| 12.2IXE    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2JA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2JK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2MB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2MC     | 12.2(15)    | 12.4(18a)   |
|            | MC2h        |             |
|------------+-------------+-------------|
|            | 12.2(14)S18 |             |
|            |             |             |
|            | 12.2(18)S13 |             |
| 12.2S      |             | 12.2(25)S15 |
|            | 12.2(20)S14 |             |
|            |             |             |
|            | 12.2(25)S13 |             |
|------------+-------------+-------------|
|            | 12.2(28)SB7 |             |
|            |             |             |
|            | 12.2(31)SB5 |             |
| 12.2SB     |             | 12.2(28)    |
|            | 12.2(33)SB; | SB12        |
|            | Available   |             |
|            | on          |             |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
|            | first fixed |             |
| 12.2SBC    | in 12.2SB;  | 12.2(28)    |
|            | Available   | SB12        |
|            | on          |             |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
| 12.2SCA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | 12.2(35)SE4 |             |
| 12.2SE     |             | 12.2(44)SE1 |
|            | 12.2(37)SE  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SEA    | first fixed |             |
|            | in 12.2SEE  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SEB    | first fixed |             |
|            | in 12.2SEE  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SEC    | first fixed |             |
|            | in 12.2SEE  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SED    | first fixed |             |
|            | in 12.2SEE  |             |
|------------+-------------+-------------|
| 12.2SEE    | 12.2(25)    |             |
|            | SEE4        |             |
|------------+-------------+-------------|
| 12.2SEF    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SEG    | 12.2(25)    | 12.2(25)    |
|            | SEG3        | SEG4        |
|------------+-------------+-------------|
|            | 12.2(25)SG2 |             |
|            |             |             |
|            | 12.2(31)SG2 |             |
| 12.2SG     |             | 12.2(44)SG  |
|            | 12.2(37)SG1 |             |
|            |             |             |
|            | 12.2(40)SG  |             |
|------------+-------------+-------------|
|            | 12.2(31)    |             |
|            | SGA2        |             |
|            |             |             |
|            | 12.2(31)    |             |
|            | SGA3        | 12.2(31)    |
| 12.2SGA    |             | SGA5        |
|            | 12.2(31)    |             |
|            | SGA6;       |             |
|            | Available   |             |
|            | on          |             |
|            | 07-APR-08   |             |
|------------+-------------+-------------|
| 12.2SL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SM     | 12.2(29)SM2 |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SO     | migrate to  | 12.2(29)SVD |
|            | any release |             |
|            | in 12.2SVA  |             |
|------------+-------------+-------------|
| 12.2SRA    | 12.2(33)    | 12.2(33)    |
|            | SRA4        | SRA7        |
|------------+-------------+-------------|
|            |             | 12.2(33)    |
|            | 12.2(33)    | SRB3;       |
| 12.2SRB    | SRB1        | Available   |
|            |             | on          |
|            |             | 31-MAR-08   |
|------------+-------------+-------------|
| 12.2SRC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2SU     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2SV     | 12.2(29b)SV | 12.2(29b)SV |
|------------+-------------+-------------|
| 12.2SVA    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SVC    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SVD    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2SW     | 12.2(25)    |             |
|            | SW11        |             |
|------------+-------------+-------------|
|            | 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)    |             |
|            | SXF10       |             |
|            |             |             |
| 12.2SXF    | 12.2(18)    | 12.2(18)    |
|            | SXF10a      | SXF13       |
|            |             |             |
|            | 12.2(18)    |             |
|            | SXF12a      |             |
|------------+-------------+-------------|
| 12.2SXH    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | 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    | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
|            | first fixed |             |
| 12.2UZ     | in 12.2SB;  | 12.2(28)    |
|            | Available   | SB12        |
|            | on          |             |
|            | 31-MAR-08   |             |
|------------+-------------+-------------|
| 12.2XA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XD     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XE     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XG     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XH     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XI     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XJ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XK     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XM     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XN     | 12.2(33)XN1 | 12.3(26)    |
|------------+-------------+-------------|
| 12.2XO     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XQ     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XR     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XS     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XT     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XU     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XV     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2XW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YA     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YC     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YD     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YE     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YF     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YG     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YH     | first fixed | 12.3(26)    |
|            | in 12.3     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YJ     | first fixed | 12.3(26)    |
|            | 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     |             |
|------------+-------------+-------------|
| 12.2YO     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.2YP     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YQ     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YR     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 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     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YV     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2YW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2YX     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.2YY     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            |             | 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  |             |
|------------+-------------+-------------|
| 12.2ZB     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZC     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 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     |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.4(15)T4  |
| 12.2ZG     | first fixed |             |
|            | in 12.3YG   | 12.4(18a)   |
|------------+-------------+-------------|
| 12.2ZH     | 12.2(13)ZH9 | 12.2(13)    |
|            |             | ZH11        |
|------------+-------------+-------------|
|            | 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)   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZP     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.2ZU     | migrate to  | 12.2(33)    |
|            | any release | SXH2        |
|            | in 12.2SXH  |             |
|------------+-------------+-------------|
| 12.2ZY     | 12.2(18)ZY1 | 12.2(18)ZY2 |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.3-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
|            | 12.3(17c)   |             |
|            |             |             |
|            | 12.3(18a)   |             |
|            |             |             |
|            | 12.3(19a)   |             |
|            |             |             |
| 12.3       | 12.3(20a)   | 12.3(26)    |
|            |             |             |
|            | 12.3(21b)   |             |
|            |             |             |
|            | 12.3(22a)   |             |
|            |             |             |
|            | 12.3(23)    |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3B      | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | 12.3(17b)   |             |
|            | BC8         |             |
|            |             |             |
| 12.3BC     | 12.3(21a)   | 12.3(23)BC1 |
|            | BC2         |             |
|            |             |             |
|            | 12.3(23)BC  |             |
|------------+-------------+-------------|
|            | 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    | 12.3(4)     |             |
|            | TPC11b      |             |
|------------+-------------+-------------|
| 12.3VA     | Vulnerable; |             |
|            | contact TAC |             |
|------------+-------------+-------------|
|            |             | 12.3(2)XA7; |
| 12.3XA     | 12.3(2)XA6  | Available   |
|            |             | on          |
|            |             | 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     |             |
|------------+-------------+-------------|
|            |             | 12.4(15)T4  |
| 12.3XE     | 12.3(2)XE5  |             |
|            |             | 12.4(18a)   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XF     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.4(15)T4  |
| 12.3XG     | first fixed |             |
|            | in 12.3YG   | 12.4(18a)   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XH     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
| 12.3XI     | 12.3(7)     |             |
|            | XI10a       |             |
|------------+-------------+-------------|
|            | 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; |
| 12.3XR     | 12.3(7)XR7  | Available   |
|            |             | on          |
|            |             | 31-MAR-08   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XS     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | 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  |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3XY     | first fixed | 12.4(18a)   |
|            | in 12.4     |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.4(15)T4  |
| 12.3YA     | first fixed |             |
|            | in 12.4     | 12.4(18a)   |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YD     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
|            | Vulnerable; | 12.3(14)    |
| 12.3YF     | first fixed | YX11        |
|            | in 12.3YX   |             |
|            |             | 12.4(15)T4  |
|------------+-------------+-------------|
| 12.3YG     | 12.3(8)YG6  | 12.4(15)T4  |
|------------+-------------+-------------|
|            | 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    |             |
|------------+-------------+-------------|
| 12.3YK     | 12.3(11)YK3 | 12.4(15)T4  |
|------------+-------------+-------------|
| 12.3YM     | 12.3(14)    | 12.3(14)    |
|            | YM10        | YM12        |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.3YQ     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.3YS     | 12.3(11)YS2 | 12.4(15)T4  |
|------------+-------------+-------------|
|            | 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)YX9 | 12.3(14)    |
|            |             | YX11        |
|------------+-------------+-------------|
| 12.3YZ     | 12.3(11)YZ2 |             |
|------------+-------------+-------------|
|  Affected  | First Fixed | Recommended |
| 12.4-Based |   Release   |   Release   |
|  Releases  |             |             |
|------------+-------------+-------------|
|            | 12.4(10c)   |             |
|            |             |             |
|            | 12.4(12b)   |             |
|            |             |             |
|            | 12.4(13c)   |             |
|            |             |             |
|            | 12.4(16)    |             |
|            |             |             |
| 12.4       | 12.4(17a)   | 12.4(18a)   |
|            |             |             |
|            | 12.4(3h)    |             |
|            |             |             |
|            | 12.4(5c)    |             |
|            |             |             |
|            | 12.4(7f)    |             |
|            |             |             |
|            | 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     | 12.4(11)MD1 | Available   |
|            |             | on          |
|            |             | 09-MAY-08   |
|------------+-------------+-------------|
| 12.4MR     | 12.4(12)MR2 | 12.4(16)MR2 |
|------------+-------------+-------------|
| 12.4SW     | 12.4(11)SW3 | 12.4(15)SW  |
|------------+-------------+-------------|
|            | 12.4(11)T3  |             |
|            |             |             |
|            | 12.4(15)T   |             |
|            |             |             |
|            | 12.4(2)T6   |             |
| 12.4T      |             | 12.4(15)T4  |
|            | 12.4(4)T8   |             |
|            |             |             |
|            | 12.4(6)T8   |             |
|            |             |             |
|            | 12.4(9)T4   |             |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.4XA     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.4XB     | 12.4(2)XB6  |             |
|------------+-------------+-------------|
| 12.4XC     | 12.4(4)XC7  |             |
|------------+-------------+-------------|
| 12.4XD     | 12.4(4)XD8  | 12.4(4)XD10 |
|------------+-------------+-------------|
| 12.4XE     | 12.4(6)XE2  | 12.4(15)T4  |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.4XF     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.4XG     | 12.4(9)XG2  | 12.4(9)XG2  |
|------------+-------------+-------------|
| 12.4XJ     | 12.4(11)XJ4 | 12.4(15)T4  |
|------------+-------------+-------------|
|            | Vulnerable; |             |
| 12.4XK     | first fixed | 12.4(15)T4  |
|            | in 12.4T    |             |
|------------+-------------+-------------|
| 12.4XL     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XM     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XN     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XT     | 12.4(6)XT1  | 12.4(6)XT2  |
|------------+-------------+-------------|
| 12.4XV     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XW     | Not         |             |
|            | Vulnerable  |             |
|------------+-------------+-------------|
| 12.4XY     | Not         |             |
|            | Vulnerable  |             |
+----------------------------------------+

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

The workaround for this vulnerability consists of filtering MDT Data
Join packets on the PE device.

The workarounds need to be applied on all Virtual Routing and
Forwarding (VRF) interfaces of all PE routers. Otherwise, attackers
can target remote PE routers and can still exploit this
vulnerability.

Even if only one PE router in the network runs an unfixed version of
IOS code, it is vulnerable to packets that come from systems that are
connected to remote PE routers. In such a case, workarounds need to
be deployed on all PE routers to successfully mitigate this
vulnerability.

The "mdt data <group> <mask>" or "mdt data <group> <mask> threshold 
<n> list <acl>" commands do not mitigate this vulnerability.

Filtering Packets to UDP Port 3232
+---------------------------------

MDT Data Join messages are sent to UDP port 3232. Creating an
access-list that filters destination UDP port 3232 and applying it on
the VRF interface of the PE router mitigates this vulnerability. Such
an access-list looks like this:

    access-list 100 deny udp any any eq 3232
    access-list 100 permit ip any any
    
    interface Serial 0/0
      ip vrf forwarding <vpn-1>
      ...
      ip access-group 100 in

Note that this access-list can also filter legitimate traffic that is
destined to UDP port 3232. In such a case, the access-list can be
modified to be more specific by providing individual BGP peer IP
addresses. This is explained in the section that follows.

Filtering BGP Peer IP Addresses on the VRF Interface
+---------------------------------------------------

In order to successfully exploit this vulnerability, an attacker
needs to send MDT Data Join messages by spoofing the packets from the
IP address of one of the existing iBGP peers. Because MDT Data Join
messages are only used between PE routers, the packets from CE
devices can safely be filtered.

Creating an access-list that filters iBGP peer IP addresses as source
addresses and applying it on the VRF interface of the PE router
mitigates this vulnerability. The access-list needs to filter all
iBGP peer IP addresses. Such an access-list looks like this example:

    access-list 100 deny udp host <ibgp-peer-1> any eq 3232 
    access-list 100 deny udp host <ibgp-peer-2> any eq 3232
    ...
    access-list 100 deny udp host <ibgp-peer-n> any eq 3232 
    access-list 100 permit ip any any
    
    interface Serial 0/0
      ip vrf forwarding <vpn-1>
      ...
      ip access-group 100 in

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-mvpn.shtml

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

Cisco has released free software updates that address this
vulnerability. 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.

This vulnerability was reported to Cisco by Thomas Morin.

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-mvpn.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-March-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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