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Cisco IOS Software Session Initiation Protocol Denial of Service Vulnerability

Advisory ID: cisco-sa-20090325-sip

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-sip

Revision 1.4

For Public Release 2009 March 25 16:00  UTC (GMT)


Summary

A vulnerability exists in the Session Initiation Protocol (SIP) implementation in Cisco IOS Software that can be exploited remotely to cause a reload of the Cisco IOS device.

Cisco has released free software updates that address this vulnerability. There are no workarounds available to mitigate the vulnerability apart from disabling SIP, if the Cisco IOS device does not need to run SIP for VoIP services. However, mitigation techniques are available to help limit exposure to the vulnerability.

This advisory is posted at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-sip.

Note: The March 25, 2009, Cisco IOS Security Advisory bundled publication includes eight Security Advisories. All of the advisories address vulnerabilities in Cisco IOS Software. Each advisory lists the releases that correct the vulnerability or vulnerabilities in the advisory.

Individual publication links are listed below:

Affected Products

This vulnerability only affects devices running Cisco IOS Software with SIP voice services enabled.

Vulnerable Products

Cisco devices running affected Cisco IOS Software versions that process SIP messages are affected. The only requirement for this vulnerability is that the Cisco IOS device process SIP messages as part of configured VoIP functionality. Note that this does not apply to the processing of SIP messages as part of the NAT and firewall feature sets.

Recent versions of Cisco IOS Software do not process SIP messages by default. Creating a dial peer by way of the command dial-peer voice will start the SIP processes and cause the Cisco IOS device to start processing SIP messages. In addition, several features within Cisco Unified Communications Manager Express, such as ePhones, once configured will also automatically start the SIP process, which will cause the device to start processing SIP messages. An example of an affected configuration is as follows:

dial-peer voice <Voice dial-peer tag> voip
 ...
!

Note: Older versions of Cisco IOS Software were affected by a bug that caused Cisco IOS Software to process SIP messages without being configured for SIP operation. Refer to http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20070131-sip for additional information on Cisco bug ID CSCsb25337 ( registered customers only) .

In addition to inspecting the Cisco IOS device configuration for a dial-peer command that causes the device to process SIP messages, administrators can also use the command show processes | include SIP to determine whether Cisco IOS Software is running the processes that handle SIP messages. In the following example, the presence of the processes CCSIP_UDP_SOCKET and CCSIP_TCP_SOCKET indicates that the Cisco IOS device is processing SIP messages:

    Router#show processes | include SIP
     147 Mwe 40F46DF4           12          2    600023468/24000  0 CCSIP_SPI_CONTRO
     148 Mwe 40F21244            0          1       0 5524/6000   0 CCSIP_DNS       
     149 Mwe 40F48254            4          1    400023108/24000  0 CCSIP_UDP_SOCKET
     150 Mwe 40F48034            4          1    400023388/24000  0 CCSIP_TCP_SOCKET

Warning: Since there are several ways a device running Cisco IOS Software can start processing SIP messages, it is recommended that the show processes | include SIP command be used to determine whether the device is processing SIP messages instead of relying on the presence of specific configuration commands.

To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the show version command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the show version command or may provide different output.

The following example identifies a Cisco product that is running Cisco IOS Software Release 12.3(26) with an installed image name of C2500-IS-L:

Router#show version
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-IS-L), Version 12.3(26), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by cisco Systems, Inc.
Compiled Mon 17-Mar-08 14:39 by dchih

!--- output truncated

The following example identifies a Cisco product that is running Cisco IOS Software Release 12.4(20)T with an installed image name of C1841-ADVENTERPRISEK9-M:

Router#show version
Cisco IOS Software, 1841 Software (C1841-ADVENTERPRISEK9-M), Version 12.4(20)T, RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Thu 10-Jul-08 20:25 by prod_rel_team

!--- output truncated

Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS Reference Guide" at the following link: http://www.cisco.com/warp/public/620/1.html.

Products Confirmed Not Vulnerable

The SIP Application Layer Gateway (ALG), which is used by the Cisco IOS NAT and firewall features of Cisco IOS Software, is not affected by this vulnerability.

Cisco devices that are running Cisco IOS XE Software and Cisco IOS XR Software are not affected.

No other Cisco products are currently known to be affected by this vulnerability.

Details

SIP is a popular signaling protocol that is used to manage voice and video calls across IP networks such as the Internet. SIP is responsible for handling all aspects of call setup and termination. Voice and video are the most popular types of sessions that SIP handles, but the protocol has the flexibility to accommodate other applications that require call setup and termination. SIP call signaling can use UDP (port 5060), TCP (port 5060), or TLS (TCP port 5061) as the underlying transport protocol.

A denial of service (DoS) vulnerability exists in the SIP implementation in Cisco IOS Software. This vulnerability is triggered by processing a specific and valid SIP message.

This vulnerability is documented in Cisco Bug ID CSCsu11522 ( registered customers only) and has been assigned Common Vulnerabilities and Exposures (CVE) ID CVE-2009-0636.

Note: The vulnerabilities described in the advisories Cisco IOS Software Multiple Features IP Sockets Vulnerability and Cisco IOS Software Multiple Features Crafted UDP Packet Vulnerability, both part of this bundle of Cisco IOS advisories, may also impact SIP operations.

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.

CSCsu11522 - A voice gateway may crash when processing valid SIP message

Calculate the environmental score of CSCsu11522

CVSS Base Score - 7.8

Access Vector

Access Complexity

Authentication

Confidentiality Impact

Integrity Impact

Availability Impact

Network

Low

None

None

None

Complete

CVSS Temporal Score - 6.4

Exploitability

Remediation Level

Report Confidence

Functional

Official-Fix

Confirmed

Impact

Successful exploitation of the vulnerability described in this document may result in a reload of the device. The issue could be repeatedly exploited to cause an extended 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.

Note: In addition to CSCsu11522 and because of its impact on SIP operation, this table of fixed software takes into consideration the vulnerability tracked by Cisco Bug CSCsk64158 , from "Cisco Security Advisory: Crafted UDP Packet Affects Multiple Cisco IOS Features" (http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-udp.) The table does not take into consideration the vulnerability disclosed by "Cisco Security Advisory: Cisco IOS IP Sockets Vulnerability Affecting Multiple Cisco IOS Features", which may impact SIP over TLS.

Major Release

Availability of Repaired Releases

Affected 12.0-Based Releases

First Fixed Release

Recommended Release

12.0

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0DA

Vulnerable; first fixed in 12.2DA

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0DB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0DC

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0S

12.0(32)S12

12.0(32)S12

12.0SC

Vulnerable; first fixed in 12.0S

12.0(32)S12

12.0SL

Vulnerable; first fixed in 12.0S

12.0(32)S12

12.0SP

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0ST

Vulnerable; first fixed in 12.0S

12.0(32)S12

12.0SX

Vulnerable; first fixed in 12.0S

12.0(32)S12

12.0SY

12.0(32)SY8

12.0(32)SY8

12.0SZ

Vulnerable; first fixed in 12.0S

12.0(32)S12

12.0T

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0W

Vulnerable; contact TAC

 

12.0WC

Vulnerable; contact TAC

 

12.0WT

Not Vulnerable

 

12.0XA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XC

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XD

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XE

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XF

Not Vulnerable

 

12.0XG

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XH

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XI

Releases prior to 12.0(4)XI2 are vulnerable, release 12.0(4)XI2 and later are not vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XJ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XK

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XL

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XM

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XN

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XQ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XR

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XS

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XT

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.0XV

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

Affected 12.1-Based Releases

First Fixed Release

Recommended Release

12.1

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1AA

Vulnerable; contact TAC

 

12.1AX

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.1AY

Vulnerable; first fixed in 12.1EA

12.1(22)EA13

12.2(44)SE6

12.1AZ

Vulnerable; first fixed in 12.1EA

12.1(22)EA13

12.2(44)SE6

12.1CX

Vulnerable; contact TAC

 

12.1DA

Vulnerable; contact TAC

 

12.1DB

Vulnerable; contact TAC

 

12.1DC

Vulnerable; contact TAC

 

12.1E

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.1EA

12.1(22)EA13

12.1(22)EA13

12.1EB

Vulnerable; contact TAC

 

12.1EC

Vulnerable; first fixed in 12.3BC

12.2(33)SCB1

12.3(23)BC6

12.1EO

Vulnerable; contact TAC

 

12.1EU

Vulnerable; first fixed in 12.2SG

12.2(31)SGA9

12.1EV

Vulnerable; contact TAC

 

12.1EW

Vulnerable; migrate to 12.2SGA

12.2(31)SGA9

12.1EX

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1EY

Vulnerable; contact TAC

 

12.1EZ

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.1GA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1GB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1T

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XC

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XD

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XE

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XF

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XG

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XH

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XI

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XJ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XL

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XM

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XP

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XQ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XR

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XS

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XT

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XU

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XV

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XW

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XX

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XY

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1XZ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YC

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YD

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YE

Releases prior to 12.1(5)YE6 are vulnerable, release 12.1(5)YE6 and later are not vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YF

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YH

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.1YI

Vulnerable; contact TAC

 

12.1YJ

Vulnerable; first fixed in 12.1EA

12.1(22)EA13

12.2(44)SE6

Affected 12.2-Based Releases

First Fixed Release

Recommended Release

12.2

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2B

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.2BC

Vulnerable; migrate to 12.2SCB or 12.3BC

12.2(33)SCB1

12.3(23)BC6

12.2BW

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2BX

Vulnerable; migrate to 12.2SB

12.2(33)SB4

12.2BY

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2BZ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2CX

Vulnerable; migrate to 12.2SCB or 12.3BC

12.2(33)SCB1

12.3(23)BC6

12.2CY

Vulnerable; migrate to 12.2SCB or 12.3BC

12.2(33)SCB1

12.3(23)BC6

12.2CZ

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.2DA

12.2(12)DA14; Available on 30-JUL-2009

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2DD

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2DX

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2EW

Vulnerable; first fixed in 12.2SG

12.2(31)SGA9

12.2EWA

Vulnerable; first fixed in 12.2SG

12.2(31)SGA9

12.2EX

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2EY

12.2(44)EY

12.2(44)SE6

12.2EZ

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2FX

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2FY

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2FZ

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2IRA

Vulnerable; first fixed in 12.2SRC

12.2(33)SRC4; Available on 18-MAY-2009

12.2IRB

Vulnerable; first fixed in 12.2SRC

12.2(33)SRC4; Available on 18-MAY-2009

12.2IXA

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2IXB

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2IXC

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2IXD

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2IXE

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2IXF

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2IXG

Vulnerable; migrate to any release in 12.2IXH

12.2(18)IXH; Available on 31-MAR-2009

12.2JA

Not Vulnerable

 

12.2JK

Not Vulnerable

 

12.2MB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2MC

12.2(15)MC2m

12.2(15)MC2m

12.2S

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.2SB

12.2(28)SB13

12.2(31)SB14

12.2(33)SB3

12.2(33)SB4

12.2SBC

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.2SCA

Vulnerable; first fixed in 12.2SCB

12.2(33)SCB1

12.2SCB

12.2(33)SCB1

12.2(33)SCB1

12.2SE

12.2(50)SE

12.2(46)SE2

12.2(44)SE5

12.2(44)SE6

12.2SEA

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SEB

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SEC

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SED

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SEE

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SEF

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SEG

Vulnerable; first fixed in 12.2SE

12.2(44)SE6

12.2SG

12.2(50)SG

12.2(52)SG; Available on 15-MAY-2009

12.2SGA

12.2(31)SGA9

12.2(31)SGA9

12.2SL

Not Vulnerable

 

12.2SM

Vulnerable; contact TAC

 

12.2SO

Vulnerable; contact TAC

 

12.2SQ

12.2(44)SQ1

 

12.2SRA

Vulnerable; first fixed in 12.2SRC

12.2(33)SRD1

12.2(33)SRC4; Available on 18-MAY-2009

12.2SRB

Vulnerable; first fixed in 12.2SRC

12.2(33)SRC4; Available on 18-MAY-2009

12.2(33)SRD1

12.2(33)SRB5a; Available on 3-April-2009

12.2SRC

12.2(33)SRC4; Available on 18-MAY-2009

12.2(33)SRC4; Available on 18-MAY-2009

12.2SRD

Not Vulnerable

 

12.2STE

Vulnerable; contact TAC

 

12.2SU

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.2SV

Vulnerable; contact TAC

 

12.2SVA

Vulnerable; contact TAC

 

12.2SVC

Vulnerable; contact TAC

 

12.2SVD

Vulnerable; contact TAC

 

12.2SVE

Vulnerable; contact TAC

 

12.2SW

Vulnerable; contact TAC

 

12.2SX

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.2SXA

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.2SXB

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.2SXD

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.2SXE

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.2SXF

12.2(18)SXF16

12.2(18)SXF16

12.2SXH

12.2(33)SXH5; Available on 20-APR-2009

12.2(33)SXH5; Available on 20-APR-2009

12.2SXI

Not Vulnerable

 

12.2SY

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.2SZ

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.2T

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2TPC

Vulnerable; contact TAC

 

12.2XA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XB

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XC

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XD

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XE

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XF

Vulnerable; migrate to 12.2SCB or 12.3BC

12.2(33)SCB1

12.3(23)BC6

12.2XG

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XH

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XI

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XJ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XK

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XL

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XM

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XN

Vulnerable; first fixed in 12.2SRC

12.2(33)SB4

12.2(33)SRD1

12.2XNA

Vulnerable; migrate to any release in 12.2SRD

12.2(33)SRD1

12.2XNB

12.2(33)XNB1

12.2(33)XNB3

12.2XNC

Not Vulnerable

 

12.2XO

12.2(46)XO

12.2(46)XO

12.2XQ

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XR

Not Vulnerable

 

12.2XS

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XT

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XU

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XV

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2XW

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2YA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2YB

Vulnerable; contact TAC

 

12.2YC

Vulnerable; contact TAC

 

12.2YD

Vulnerable; contact TAC

 

12.2YE

Vulnerable; contact TAC

 

12.2YF

Vulnerable; contact TAC

 

12.2YG

Vulnerable; contact TAC

 

12.2YH

Vulnerable; contact TAC

 

12.2YJ

Vulnerable; contact TAC

 

12.2YK

Vulnerable; contact TAC

 

12.2YL

Vulnerable; contact TAC

 

12.2YM

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.2YN

Vulnerable; contact TAC

 

12.2YO

Vulnerable; contact TAC

 

12.2YP

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2YQ

Vulnerable; contact TAC

 

12.2YR

Vulnerable; contact TAC

 

12.2YS

Not Vulnerable

 

12.2YT

Vulnerable; contact TAC

 

12.2YU

Vulnerable; contact TAC

 

12.2YV

Vulnerable; contact TAC

 

12.2YW

Vulnerable; contact TAC

 

12.2YX

Vulnerable; contact TAC

 

12.2YY

Vulnerable; contact TAC

 

12.2YZ

Vulnerable; contact TAC

 

12.2ZA

Vulnerable; first fixed in 12.2SXF

12.2(18)SXF16

12.2ZB

Vulnerable; contact TAC

 

12.2ZC

Vulnerable; contact TAC

 

12.2ZD

Vulnerable; contact TAC

 

12.2ZE

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2ZF

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.2ZG

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.2ZH

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.2ZJ

Vulnerable; contact TAC

 

12.2ZL

Vulnerable; contact TAC

 

12.2ZP

Vulnerable; contact TAC

 

12.2ZU

Vulnerable; first fixed in 12.2SXH

12.2(33)SXH5; Available on 20-APR-2009

12.2ZX

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.2ZY

Vulnerable; contact TAC

 

12.2ZYA

12.2(18)ZYA1

12.2(18)ZYA1

Affected 12.3-Based Releases

First Fixed Release

Recommended Release

12.3

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.3B

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3BC

12.3(23)BC6

12.3(23)BC6

12.3BW

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3EU

Not Vulnerable

 

12.3JA

Not Vulnerable

 

12.3JEA

Not Vulnerable

 

12.3JEB

Not Vulnerable

 

12.3JEC

Not Vulnerable

 

12.3JK

Not Vulnerable

 

12.3JL

Vulnerable; contact TAC

 

12.3JX

Not Vulnerable

 

12.3T

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3TPC

Vulnerable; contact TAC

 

12.3VA

Vulnerable; contact TAC

 

12.3XA

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.3XB

Vulnerable; contact TAC

 

12.3XC

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XD

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XE

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.3XF

Vulnerable; contact TAC

 

12.3XG

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XI

Vulnerable; first fixed in 12.2SB

12.2(33)SB4

12.3XJ

Vulnerable; first fixed in 12.3YX

12.3(14)YX14

12.3XK

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XL

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XQ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XR

Vulnerable; first fixed in 12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.3XS

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XU

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XW

Vulnerable; first fixed in 12.3YX

12.3(14)YX14

12.3XX

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XY

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3XZ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YA

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YD

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YF

Vulnerable; first fixed in 12.3YX

12.3(14)YX14

12.3YG

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YH

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YI

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YJ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YK

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YM

12.3(14)YM13

12.3(14)YM13

12.3YQ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YS

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YT

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YU

Vulnerable; first fixed in 12.4XB

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YX

12.3(14)YX14

12.3(14)YX14

12.3YZ

Vulnerable; contact TAC

 

12.3ZA

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

Affected 12.4-Based Releases

First Fixed Release

Recommended Release

12.4

12.4(18e)

12.4(23)

12.4(23a); Available on 05-JUN-2009

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.4JA

Not Vulnerable

 

12.4JDA

Not Vulnerable

 

12.4JK

Not Vulnerable

 

12.4JL

Not Vulnerable

 

12.4JMA

Vulnerable; contact TAC

 

12.4JMB

Vulnerable; contact TAC

 

12.4JX

Not Vulnerable

 

12.4MD

12.4(11)MD7

12.4(11)MD7

12.4MR

12.4(19)MR1

12.4(19)MR2

12.4SW

Vulnerable; contact TAC

 

12.4T

12.4(20)T2

12.4(15)T8

12.4(22)T

12.4(15)T9; Available on 29-APR-2009

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XA

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XB

12.4(15)T8

12.4(20)T2

12.4(15)T9; Available on 29-APR-2009

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XC

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XD

12.4(4)XD12; Available on 27-MAR-2009

12.4(4)XD12; Available on 27-MAR-2009

12.4XE

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XF

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XG

12.4(15)T8

12.4(20)T2

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XJ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XK

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XL

12.4(15)XL4

12.4(15)XL4

12.4XM

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XN

Vulnerable; contact TAC

 

12.4XP

Vulnerable; contact TAC

 

12.4XQ

12.4(15)XQ2

12.4(15)XQ2

12.4XR

12.4(15)XR4

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XT

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XV

Vulnerable; contact TAC

 

12.4XW

12.4(11)XW10

12.4(11)XW10

12.4XY

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XZ

12.4(15)XZ2

12.4(15)XZ2

12.4YA

12.4(20)YA2

12.4(20)YA3

12.4YB

Not Vulnerable

 

12.4YD

Not Vulnerable

 

Workarounds

If the affected Cisco IOS device requires SIP for VoIP services, SIP cannot be disabled, and therefore, no workarounds are available. Users are advised to apply mitigation techniques to help limit exposure to the vulnerability. Mitigation consists of allowing only legitimate devices to connect to the routers. To increase effectiveness, the mitigation must be coupled with anti-spoofing measures on the network edge. This action is required because SIP can use UDP as the transport protocol.

Additional mitigations that can be deployed on Cisco devices within the network are available in the companion document "Cisco Applied Mitigation Bulletin: Identifying and Mitigating Exploitation of the Cisco IOS SIP and Crafted UDP Vulnerabilities", which is available at the following location: http://tools.cisco.com/security/center/content/CiscoAppliedMitigationBulletin/cisco-amb-20090325-sip-and-udp.

Disable SIP Listening Ports

For devices that do not require SIP to be enabled, the simplest and most effective workaround is to disable SIP processing on the device. Some versions of Cisco IOS Software allow administrators to accomplish this with the following commands:

sip-ua
 no transport udp
 no transport tcp

Warning: When applying this workaround to devices that are processing Media Gateway Control Protocol (MGCP) or H.323 calls, the device will not stop SIP processing while active calls are being processed. Under these circumstances, this workaround should be implemented during a maintenance window when active calls can be briefly stopped.

After applying this workaround, administrators are advised to use the show commands, as discussed in the Affected Products section of this advisory, to confirm that the Cisco IOS device is no longer processing SIP messages.

Control Plane Policing

For devices that need to offer SIP services it is possible to use Control Plane Policing (CoPP) to block SIP traffic to the device from untrusted sources. Cisco IOS 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 can be adapted to the network:


!-- The 192.168.1.0/24 network and the 172.16.1.1 host are trusted.
!-- Everything else is not trusted. The following access list is used
!-- to determine what traffic needs to be dropped by a control plane
!-- policy (the CoPP feature.) If the access list matches (permit)
!-- then traffic will be dropped and if the access list does not
!-- match (deny) then traffic will be processed by the router.

access-list 100 deny udp 192.168.1.0 0.0.0.255 any eq 5060
access-list 100 deny tcp 192.168.1.0 0.0.0.255 any eq 5060
access-list 100 deny tcp 192.168.1.0 0.0.0.255 any eq 5061
access-list 100 deny udp host 172.16.1.1 any eq 5060
access-list 100 deny tcp host 172.16.1.1 any eq 5060
access-list 100 deny tcp host 172.16.1.1 any eq 5061
access-list 100 permit udp any any eq 5060
access-list 100 permit tcp any any eq 5060
access-list 100 permit tcp any any eq 5061

!-- Permit (Police or Drop)/Deny (Allow) all other Layer3 and Layer4
!-- 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-sip-class
  match access-group 100

!-- Create a Policy-Map that will be applied to the
!-- Control-Plane of the device.

policy-map drop-sip-traffic
 class drop-sip-class
  drop

!-- Apply the Policy-Map to the Control-Plane of the
!-- device.

control-plane
 service-policy input drop-sip-traffic

Warning: Because SIP can use UDP as a transport protocol, it is possible to easily spoof the IP address of the sender, which may defeat access control lists that permit communication to these ports from trusted IP addresses.

In the above CoPP example, the access control entries (ACEs) that 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. Additional information on the configuration and use of the CoPP feature can be found at http://www.cisco.com/web/about/security/intelligence/coppwp_gs.html and http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gtrtlimt.html.

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/docs/general/warranty/English/EU1KEN_.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@cisco.com or security-alert@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 with Service Contracts

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@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/en/US/support/tsd_cisco_worldwide_contacts.html 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 discovered during handling of customer service requests.

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://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-sip

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@cisco.com
  • first-bulletins@lists.first.org
  • bugtraq@securityfocus.com
  • vulnwatch@vulnwatch.org
  • cisco@spot.colorado.edu
  • cisco-nsp@puck.nether.net
  • full-disclosure@lists.grok.org.uk
  • comp.dcom.sys.cisco@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 1.4

2009-June-26

Removed references to the March/09 combined fixed software table.

Revision 1.3

2009-June-1

Updated expected public availability date for release 12.4(23a).

Revision 1.2

2009-May-1

Updated expected public availability date for release 12.4(23a).

Revision 1.1

2009-April-03

Releases 12.2XR, 12.4JL, 12.4JK, 12.4JX, 12.4JDA, 12.4JA, 12.3JX, 12.3JK, 12.3JEC, 12.3JEB, 12.3JEA, 12.3JA, 12.2JA, and 12.2JK have been confirmed to be not vulnerable. Adjusted fixed software table accordingly.

Revision 1.0

2009-March-25

Initial 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/web/about/security/psirt/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.