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Cisco Security Advisory

TCP State Manipulation Denial of Service Vulnerabilities in Multiple Cisco Products

Advisory ID: cisco-sa-20090908-tcp24

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090908-tcp24

Revision 1.1

For Public Release 2009 September 8 00:00  UTC (GMT)

Related Resources:

View related Applied Mitigation Bulletin

Summary

Multiple Cisco products are affected by denial of service (DoS) vulnerabilities that manipulate the state of Transmission Control Protocol (TCP) connections. By manipulating the state of a TCP connection, an attacker could force the TCP connection to remain in a long-lived state, possibly indefinitely. If enough TCP connections are forced into a long-lived or indefinite state, resources on a system under attack may be consumed, preventing new TCP connections from being accepted. In some cases, a system reboot may be necessary to recover normal system operation. To exploit these vulnerabilities, an attacker must be able to complete a TCP three-way handshake with a vulnerable system.

In addition to these vulnerabilities, Cisco Nexus 5000 devices contain a TCP DoS vulnerability that may result in a system crash. This additional vulnerability was found as a result of testing the TCP state manipulation vulnerabilities.

Cisco has released free software updates for download from the Cisco website that address these vulnerabilities. Workarounds that mitigate these vulnerabilities are available.

This advisory is posted at http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090908-tcp24.

Affected Products

Vulnerable Products

The following Cisco products have a TCP implementation that is affected by these vulnerabilities. Refer to the Software Versions and Fixes section for information on fixed software.

Cisco IOS Software

To determine the Cisco IOS® Software release that is running on a Cisco product, administrators can log into 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/web/about/security/intelligence/ios-ref.html

Cisco IOS-XE Software

The version of Cisco IOS-XE Software that is running on a Cisco product can be determined using the show version command from the Command Line Interface (CLI).

Cisco CatOS Software

The version of Cisco CatOS Software that is running on a Cisco product can be determined using the show version command from the CLI.

Cisco Adaptive Security Appliance (ASA) and Cisco PIX

Cisco ASA and Cisco PIX security appliances running versions 7.1, 7.2, 8.0, and 8.1 are affected when configured for any of the following features:

  • SSL VPNs
  • ASDM Administrative Access
  • Telnet Access
  • SSH Access
  • Cisco Tunneling Control Protocol (cTCP) for Remote Access VPNs
  • Virtual Telnet
  • Virtual HTTP
  • Transport Layer Security (TLS) Proxy for Encrypted Voice Inspection
  • Cut-Through Proxy for Network Access

The version of software that is running on a Cisco ASA and Cisco PIX security appliances can be determined using the show version command from the CLI.

Cisco NX-OS Software

The version of Cisco NX-OS Software that is running on Cisco Nexus 5000 and 7000 series devices can be determined using the show version command from the CLI.

Scientific Atlanta Products

Scientific Atlanta customers are instructed to contact Scientific Atlanta's Technical Support for questions regarding the impact, mitigation and remediation of the vulnerabilities discussed in this document.

Contact information for Scientific Atlanta Technical Support can be found at the following web site:

http://www.cisco.com/en/US/products/ps10459/serv_group_home.html

Linksys Products

Cisco has investigated the Linksys product family and found that no Linksys products are affected by the TCP vulnerabilities. Customers with additional questions on Linksys products should contact:

security@linksys.com

Products Confirmed Not Vulnerable

The following Cisco products are not affected:

  • Cisco IOS XR
  • Cisco IOS Software Modularity
  • Cisco ASA Software version 8.2
  • Cisco ASA and Cisco PIX Software version 7.0
  • Cisco PIX Software version 6.x and earlier
  • Cisco Firewall Services Module (FWSM)
  • Cisco Multilayer Distribution Switches (MDS)
  • Cisco Application Control Engine (ACE) Modules and Appliances
  • Cisco ACE XML Gateway
  • Cisco Access Control Server (ACS) Solution Engine
  • Cisco Guard
  • Cisco Security Monitoring, Analysis, and Response System (CS-MARS)
  • Cisco ONS 15000
  • Cisco Content Services Switches (CSS)
  • Cisco Wide Area Application Services (WAAS)
  • Cisco Wireless LAN Controller (WLC)
  • IronPort C, M, S and X Series Appliances
  • Cisco Global Site Selector (GSS)
  • Cisco SSL Services Module (SSLM)
  • Cisco Network Analysis Module (NAM)
  • Cisco Content Switch Module (CSM)
  • Cisco Web Application Firewall (WAF)
  • Cisco Service Control Engine (SCE)
  • Cisco Wireless Services Modules (WiSM)
  • Cisco Application and Content Networking System (ACNS)
  • Cisco Content Engine (CE)

Cisco PSIRT tested Cisco products that are based on Linux and Microsoft Windows operating systems and found that although TCP connections in a FINWAIT1 state may temporarily consume system resources the operating systems eventually clear the TCP connections. If enough system resources are consumed, a sustained DoS condition may be possible. This outcome is highly dependent on the configuration and usage of a system. For more information about how these vulnerabilities affect Microsoft Windows operating systems, please consult the following Microsoft website at the following link:

http://go.microsoft.com/fwlink/?LinkId=155978 leavingcisco.com

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

Details

Multiple Cisco products are affected by DoS vulnerabilities in the TCP protocol. By manipulating the state of TCP connections, an attacker could force a system that is under attack to maintain TCP connections for long periods of time, or indefinitely in some cases. With a sufficient number of open TCP connections, the attacker may be able to cause a system to consume internal buffer and memory resources, resulting in new TCP connections being denied access to a targeted port or an entire system. A system reboot may be required to restore full system functionality. A full TCP three-way handshake is required to exploit these vulnerabilities.

Network devices are not directly impacted by TCP state manipulation DoS attacks transiting a device; however, network devices that maintain the state of TCP connections may be impacted. If the attacker can establish enough TCP connections through a transit device that maintains TCP state, device resources may be exhausted and prevent the device from processing new TCP connections, resulting in a DoS condition. If an affected device that forwards traffic (that is, routes) in a network is the target of a TCP state manipulation attack, the attacker could cause a network-impacting DoS condition.

Cisco IOS Software

All Cisco IOS Software versions are affected by this vulnerability. A device running Cisco IOS Software that is under attack will have numerous hung TCP connections in the FINWAIT1 state. The show tcp brief command can be used to display the hung TCP connections. The following is example output showing an attack in progress.

Router#show tcp brief | include FIN
63D697C4  192.168.1.10.80            192.168.1.20.38479         FINWAIT1
63032A28  192.168.1.10.80            192.168.1.20.54154         FINWAIT1
645F8068  192.168.1.10.80            192.168.1.20.56287         FINWAIT1
630323F4  192.168.1.10.80            192.168.1.20.6372          FINWAIT1
63D69190  192.168.1.10.80            192.168.1.20.23489         FINWAIT1

The vulnerabilities for Cisco IOS Software are documented in Cisco Bug ID CSCsv04836 ( registered customers only) .

Cisco IOS-XE Software

All Cisco IOS-XE Software versions are affected by this vulnerability. A device running Cisco IOS-XE Software that is under attack will have numerous hung TCP connections in the FINWAIT1 state. The show tcp brief command can be used to display the hung TCP connections. The following is example output showing an attack in progress.

Router#show tcp brief | include FIN
63D697C4  192.168.1.10.80            192.168.1.20.38479         FINWAIT1
63032A28  192.168.1.10.80            192.168.1.20.54154         FINWAIT1
645F8068  192.168.1.10.80            192.168.1.20.56287         FINWAIT1
630323F4  192.168.1.10.80            192.168.1.20.6372          FINWAIT1
63D69190  192.168.1.10.80            192.168.1.20.23489         FINWAIT1

The vulnerabilities for Cisco IOS-XE Software are documented in Cisco Bug ID CSCsv07712 ( registered customers only) .

Cisco CatOS Software

All Cisco CatOS Software versions are affected by these vulnerabilities. A device running Cisco CatOS Software that is under attack will have numerous hung TCP connections in the FIN_WAIT_1 state. The show netstat command can be used to display the hung TCP connections. The following is example output showing an attack in progress.

Console> (enable) show netstat
Active Internet connections (including servers)
Proto Recv-Q Send-Q  Local Address          Foreign Address        (state)
tcp        0     83  192.168.1.10.23        192.168.1.20.46056       FIN_WAIT_1
tcp        0     83  192.168.1.10.23        192.168.1.20.16305       FIN_WAIT_1
tcp        0     83  192.168.1.10.23        192.168.1.20.14628       FIN_WAIT_1
tcp        0     83  192.168.1.10.23        192.168.1.20.7275        FIN_WAIT_1
tcp        0     83  192.168.1.10.23        192.168.1.20.39559       FIN_WAIT_1

The vulnerabilities for Cisco CatOS Software are documented in Cisco Bug ID CSCsv66169 ( registered customers only) .

Cisco ASA and Cisco PIX Software

Certain Cisco ASA and Cisco PIX Software versions are affected by these vulnerabilities. A device running Cisco ASA and Cisco PIX Software that is under attack will have numerous TCP connections in the established state. The show asp table socket command can be used to display the TCP connections. The following is example output showing a potential attack in progress.

FIREWALL# show asp table socket | grep ESTAB
TCP       123a8a6c  192.168.1.10:80           192.168.1.20:46181    ESTAB
TCP       123e6d54  192.168.1.10:80           192.168.1.20:29546    ESTAB
TCP       1244f78c  192.168.1.10:80           192.168.1.20:40271    ESTAB
TCP       124f8d2c  192.168.1.10:80           192.168.1.20:46599    ESTAB
TCP       12507f2c  192.168.1.10:80           192.168.1.20:5607     ESTAB

It is possible for normal traffic to cause established TCP connections to appear on Cisco ASA or PIX devices, especially VPN connections terminated to the device. In order to confirm if established TCP connections are part of an attack, administrators should use a monitoring point outside the firewall such as a packet sniffer or Netflow collection agent to examine the profile of the suspicious TCP connections and determine if an attack is occurring.

Note: The show asp table socket command was introduced in Cisco ASA and Cisco PIX Software 8.0(1).

Further detail about hung TCP connections can be found with show conn detail all long command. The IP address used to qualify the example below is the address of the firewall interface under attack.

FIREWALL# show conn detail all long | grep 192.168.1.10
TCP outside:192.168.1.20/62345 (192.168.1.20/62345) NP Identity Ifc:192.168.1.10/80 (192.168.1.10/80), flags UB, idle 0s, uptime 0s, timeout 1m0s, bytes 0
TCP outside:192.168.1.20/56268 (192.168.1.20/56268) NP Identity Ifc:192.168.1.10/80 (192.168.1.10/80), flags UB, idle 0s, uptime 0s, timeout 1m0s, bytes 0
TCP outside:192.168.1.20/63445 (192.168.1.20/63445) NP Identity Ifc:192.168.1.10/80 (192.168.1.10/80), flags UB, idle 0s, uptime 0s, timeout 1m0s, bytes 0
TCP outside:192.168.1.20/49151 (192.168.1.20/49151) NP Identity Ifc:192.168.1.10/80 (192.168.1.10/80), flags UB, idle 0s, uptime 0s, timeout 1m0s, bytes 0
TCP outside:192.168.1.20/57147 (192.168.1.20/57147) NP Identity Ifc:192.168.1.10/80 (192.168.1.10/80), flags UB, idle 0s, uptime 0s, timeout 1m0s, bytes 0

Note: Both troubleshooting commands referenced about will display TCP connections that are terminated to a firewall interface and transiting through the firewall.

The vulnerabilities for Cisco ASA and Cisco PIX Software are documented in Cisco Bug ID CSCsv02768 ( registered customers only) .

Cisco NX-OS Software

All Cisco Nexus 5000 and 7000 platforms running Cisco NX-OS Software are affected by these vulnerabilities. A Nexus 5005 or 7000 device running Cisco NX-OS Software that is under attack will have numerous hung TCP connections in the FIN_WAIT_1 state. The show tcp connection detail command can be used to display the hung TCP connections. The following is example output showing an attack in progress.

NEXUS# show tcp connection detail | include FIN

  State: FIN_WAIT_1
  State: FIN_WAIT_1
  State: FIN_WAIT_1
  State: FIN_WAIT_1
  State: FIN_WAIT_1

The hung TCP connection vulnerabilities for Nexus 5000 and Nexus 7000 devices are documented in Cisco Bug ID CSCsv08325 ( registered customers only) and Cisco Bug ID CSCsv08579 ( registered customers only) respectively.

While investigating the TCP state manipulation vulnerabilities, it was discovered that Cisco NX-OS on Nexus 5000 platforms may be vulnerable to a system crash when receiving a specific sequence of TCP packets. This vulnerability is documented in Cisco Bug ID CSCsv08059 ( registered customers only) and has been assigned CVE identifier CVE-2009-0627.

The TCP state manipulation vulnerabilities have been assigned Common Vulnerabilities and Exposures (CVE) identifier CVE-2008-4609.

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

CSCsv04836 - Connections getting stuck at FINWAIT1 state ( registered customers only)

Calculate the environmental score of CSCsv04836

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

CSCsv07712 - Connections getting stuck at FINWAIT1 state ( registered customers only)

Calculate the environmental score of CSCsv07712

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

CSCsv66169 - TCP Connections get stuck in FINWAIT1 state ( registered customers only)

Calculate the environmental score of CSCsv66169

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

CSCsv02768 - TCP connections getting stuck in FINWAIT1 state ( registered customers only)

Calculate the environmental score of CSCsv02768

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

CSCsv08325 - TCP connections may get stuck in any state after ESTAB indefinitely ( registered customers only)

Calculate the environmental score of CSCsv08325

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

CSCsv08579 - TCP connections get stuck in FINWAIT1 state indefinitely ( registered customers only)

Calculate the environmental score of CSCsv08579

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

CSCsv08059 - NEXUS 5000 crashes after certain TCP packets ( registered customers only)

Calculate the environmental score of CSCsv08059

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 TCP state manipulation vulnerabilities may result in a DoS condition where new TCP connections are not accepted on an affected system. Repeated exploitation may result in a sustained DoS condition. A reboot may be required to recover affected systems.

In addition, Cisco Nexus 5000 systems may crash upon receiving a specific sequence of TCP packets.

Software Versions and Fixes

hen 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.

Cisco IOS Software

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 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(23b)

12.4(25b)

12.0DA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0DB

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.0DC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0S

12.0(33)S3

12.0(32)S12

12.0(33)S5

12.0(32)S14; Available on 25-SEP-2009

12.0SC

Vulnerable; first fixed in 12.0S

12.0(33)S5

12.0(32)S14; Available on 25-SEP-2009

12.0SL

Vulnerable; first fixed in 12.0S

12.0(33)S5

12.0(32)S14; Available on 25-SEP-2009

12.0SP

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0ST

Vulnerable; first fixed in 12.0S

12.0(33)S5

12.0(32)S14; Available on 25-SEP-2009

12.0SX

Vulnerable; first fixed in 12.0S

12.0(33)S5

12.0(32)S14; Available on 25-SEP-2009

12.0SY

12.0(32)SY8

12.0(32)SY9a

12.0(32)SY10 ; Available on 25-SEP-2009

12.0(32)SY9a

12.0(32)SY10; Available on 25-SEP-2009

12.0SZ

12.0(30)SZ10

12.0(33)S5

12.0(32)S14; Available on 25-SEP-2009

12.0T

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0W

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.0WC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.0WT

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XD

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XE

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XF

Vulnerable; first fixed in 12.4

12.0XG

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XH

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XI

Vulnerable; first fixed in 12.4

12.4(25b)

12.4(23b)

12.0XJ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XK

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XL

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XM

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XN

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XQ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XR

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.0XS

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.0XT

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.0XV

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

Affected 12.1-Based Releases

First Fixed Release

Recommended Release

12.1

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1AA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1AX

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1AY

Vulnerable; first fixed in 12.1EA

12.1(22)EA13

12.1AZ

Vulnerable; first fixed in 12.1EA

12.1(22)EA13

12.1CX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1DA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1DB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1DC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1E

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1EA

12.1(22)EA13

12.1(22)EA13

12.1EB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1EC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1EO

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1EU

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1EV

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1EW

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1EX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1EY

12.2(44)EY

12.2(46)EY

12.1EZ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1GA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1GB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1T

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XD

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XE

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XF

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XG

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XH

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XI

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XJ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XL

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XM

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XP

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XQ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XR

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XS

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.1XT

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XU

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XV

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XW

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XY

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1XZ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YD

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YE

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.1YF

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YH

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.1YI

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.1YJ

Vulnerable; first fixed in 12.1EA

12.1(22)EA13

Affected 12.2-Based Releases

First Fixed Release

Recommended Release

12.2

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2B

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2BC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2BW

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2BX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2BY

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2BZ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2CX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2CY

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2CZ

Vulnerable; first fixed in 12.2SB

12.2(28)SB14; Available on 20-OCT-2009

12.2DA

12.2(12)DA14

12.4(25b)

12.4(23b)

12.2DD

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2DX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2EW

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2EWA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2EX

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2EY

Releases prior to 12.2(44)EY are vulnerable, release 12.2(44)EY and later are not vulnerable

12.2(50)SE3

12.2(52)SE; Available on 13-OCT-2009

12.2EZ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2FX

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2FY

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2FZ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2IRA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2IRB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2IRC

12.2(33)IRC

 

12.2IXA

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXB

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXC

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXD

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXE

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXF

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXG

Vulnerable; migrate to any release in 12.2IXH

 

12.2IXH

12.2(18)IXH

 

12.2JA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2JK

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2MB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2MC

12.2(15)MC2m

12.4(25b)

12.4(23b)

12.2S

Vulnerable; first fixed in 12.2SB

12.2(28)SB14; Available on 20-OCT-2009

12.2SB

12.2(28)SB13

12.2(31)SB14

12.2(33)SB1b

12.2(34)SB2

12.2(31)SB16

12.2(28)SB14; Available on 20-OCT-2009

12.2(33)SB7

12.2SBC

Vulnerable; first fixed in 12.2SB

12.2(28)SB14; Available on 20-OCT-2009

12.2SCA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SCB

12.2(33)SCB1

12.2(33)SCB4

12.2SE

12.2(44)SE5

12.2(46)SE2

12.2(50)SE

12.2(50)SE3

12.2(52)SE; Available on 13-OCT-2009

12.2SEA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SEB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SEC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SED

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SEE

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SEF

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SEG

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SG

12.2(50)SG

12.2(53)SG1

12.2SGA

12.2(31)SGA9

12.2(31)SGA11; Available on 04-DEC-2009

12.2SL

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2SM

Releases prior to 12.2(29)SM5 are vulnerable, release 12.2(29)SM5 and later are not vulnerable

12.2(29)SM5

12.2SO

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SQ

12.2(44)SQ2

 

12.2SRA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SRB

12.2(33)SRB5a

12.2(33)SRD3

12.2(33)SRC5; Available on 29-OCT-2009

12.2SRC

12.2(33)SRC3

12.2(33)SRC5; Available on 29-OCT-2009

12.2SRD

12.2(33)SRD1

12.2(33)SRD3

12.2STE

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SU

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2SV

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SVA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SVC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SVD

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2SVE

12.2(29)SVE1

 

12.2SW

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.2SX

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

12.2(18)SXF17; Available on 30-SEP-2009

12.2SXA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

12.2(18)SXF17; Available on 30-SEP-2009

12.2SXB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

12.2(18)SXF17; Available on 30-SEP-2009

12.2SXD

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

12.2(18)SXF17; Available on 30-SEP-2009

12.2SXE

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

12.2(18)SXF17; Available on 30-SEP-2009

12.2SXF

12.2(18)SXF16

12.2(18)SXF17; Available on 30-SEP-2009

12.2SXH

12.2(33)SXH5

12.2(33)SXH6; Available on 30-OCT-2009

12.2SXI

12.2(33)SXI1

12.2SXI2a

12.2SY

Vulnerable; first fixed in 12.2SB

12.2(28)SB14; Available on 20-OCT-2009

12.2SZ

Vulnerable; first fixed in 12.2SB

12.2(28)SB14; Available on 20-OCT-2009

12.2T

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2TPC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2XA

Vulnerable; first fixed in 12.4

12.4(25b)

12.4(23b)

12.2XB

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XD

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XE

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XF

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XG

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XH

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XI

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XJ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XK

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XL

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XM

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XN

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2XNA

Please see Cisco IOS-XE Software Availability

 

12.2XNB

Please see Cisco IOS-XE Software Availability

 

12.2XNC

Please see Cisco IOS-XE Software Availability

 

12.2XND

Please see Cisco IOS-XE Software Availability

 
 

12.2XO

12.2(52)XO

12.2(50)SG5; Available on 28-SEP-2009

12.2XQ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XR

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XS

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XT

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XU

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XV

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2XW

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2YA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2YB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YD

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YE

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YF

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YG

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YH

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YJ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YK

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YL

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YM

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2YN

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YO

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YP

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.2YQ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YR

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YS

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YT

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YU

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YV

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YW

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YX

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YY

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2YZ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

12.2(18)SXF17; Available on 30-SEP-2009

12.2ZB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZD

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZE

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2ZF

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2ZG

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2ZH

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2ZJ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZL

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZM

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.2ZP

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZU

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZX

Vulnerable; first fixed in 12.2SB

12.2(28)SB14; Available on 20-OCT-2009

12.2ZY

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.2ZYA

12.2(18)ZYA1

12.2(18)ZYA2

Affected 12.3-Based Releases

First Fixed Release

Recommended Release

12.3

Vulnerable; first fixed in 12.4

12.4(25b)

12.4(23b)

12.3B

Vulnerable; first fixed in 12.4

12.4(25b)

12.4(23b)

12.3BC

12.3(21a)BC9

12.3(23)BC6

12.3(21a)BC9

12.3BW

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3EU

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3JA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3JEA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3JEB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3JEC

12.3(8)JEC3

 

12.3JED

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3JK

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3JL

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3JX

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3T

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3TPC

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3VA

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3XA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3XC

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XD

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XE

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XF

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3XG

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XI

Vulnerable; first fixed in 12.2SB

12.2(33)SB7

12.2(31)SB16

12.3XJ

Vulnerable; first fixed in 12.4XR

12.4(15)XR7

12.4(22)XR

12.3XK

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XL

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XQ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XR

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XS

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XU

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3XW

Vulnerable; first fixed in 12.4XR

12.4(15)XR7

12.4(22)XR

12.3XX

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XY

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3XZ

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3YA

Vulnerable; first fixed in 12.4

12.4(23b)

12.4(25b)

12.3YD

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YF

Vulnerable; first fixed in 12.4XR

12.4(15)XR7

12.4(22)XR

12.3YG

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YH

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YI

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YJ

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YK

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YM

12.3(14)YM13

12.4(23b)

12.4(25b)

12.3YQ

Vulnerable; first fixed in 12.4T

12.4(23b)

12.4(25b)

12.3YS

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YT

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YU

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.3YX

12.3(14)YX14

12.4(15)XR7

12.4(22)XR

12.3YZ

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.3ZA

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

Affected 12.4-Based Releases

First Fixed Release

Recommended Release

12.4

12.4(18d)

12.4(23a)

12.4(25)

12.4(25b)

12.4(23b)

12.4GC

12.4(22)GC1

12.4(24)GC1

12.4(24)GC1

12.4JA

12.4(16b)JA1

12.4(21a)JA

 

12.4JDA

12.4(10b)JDA3

 

12.4JDC

12.4(10b)JDC

 

12.4JDD

12.4(10b)JDD

 

12.4JK

12.4(3)JK4

 

12.4JL

12.4(3)JL1

 

12.4JMA

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.4JMB

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.4JX

12.4(21a)JX

 

12.4MD

12.4(11)MD7

12.4(15)MD2

12.4(22)MD

12.4(11)MD9

12.4(15)MD3

12.4(22)MD1

12.4MDA

12.4(22)MDA

12.4(22)MDA1

12.4MR

12.4(19)MR2

12.4(19)MR3

12.4SW

12.4(15)SW3

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4T

12.4(5)T5e

12.4(15)T6a

12.4(22)T1

12.4(20)T2

12.4(24)T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XA

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XB

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XC

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XD

12.4(4)XD12

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XE

12.4(6)XE4

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XF

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XG

12.4(9)XG4

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XJ

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XK

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XL

12.4(15)XL4

 

12.4XM

12.4(15)XM3

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XN

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.4XP

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.4XQ

12.4(15)XQ2

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XR

12.4(15)XR4

12.4(22)XR

12.4(15)XR7

12.4XT

Vulnerable; first fixed in 12.4T

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XV

Vulnerable; Contact your support organization per the instructions in Obtaining Fixed Software section of this advisory

 

12.4XW

12.4(11)XW10

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XY

12.4(15)XY4

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4XZ

12.4(15)XZ2

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4YA

12.4(20)YA2

12.4(15)T10

12.4(20)T4

12.4(22)T3

12.4(24)T2; Available on 23-OCT-2009

12.4YB

12.4(22)YB

12.4(22)YB4

12.4YD

12.4(22)YD

12.4(22)YD1

12.4YE

12.4(22)YE

12.4(22)YE1

Cisco IOS-XE Software

IOS-XE Release

First Fixed Release

2.1.x

2.2.3

2.2.x

2.2.3

2.3.x

Not Vulnerable

2.4.x

Not Vulnerable

Cisco CatOS Software

Affected Releases

First Fixed Release

7.x

7.6(24a)

8.x

8.7(2a)

Cisco ASA and Cisco PIX Software

Affected Releases

First Fixed Release

7.1

7.1(2.79)

7.2

7.2(4.18)

8.0

8.0(4.9)

8.1

8.1(2.3)

8.2

Not Vulnerable

Cisco NX-OS Software

Affected Releases

First Fixed Release

Cisco Nexus 5000

4.0(1a)N2(1)

Cisco Nexus 7000

4.1(4)


Workarounds

It is possible to mitigate these vulnerabilities with the following workarounds.

Cisco IOS Software

The Cisco Guide to Harden Cisco IOS Devices provides examples of many useful techniques to mitigate against the TCP state manipulation vulnerabilities. These include:

  • Infrastructure Access Control Lists (iACL)
  • Receive Access Control Lists (rACL)
  • Transit Access Control Lists (tACL)
  • VTY Access Control Lists
  • Control Plane Policing (CoPP)
  • Control Plane Protection (CPPr)
  • Management Plane Policing (MPP)

For more information on the topics listed above, consult the Cisco Guide to Harden Cisco IOS Devices at the following link:

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml

Cisco CatOS Software

Cisco CatOS software provides VLAN Access Control Lists (VACL) to mitigate against the TCP state manipulation vulnerabilities. For more information on configuring VACLs on CatOS 7.x software versions, please consult the following link:

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/catos/7.x/configuration/guide/acc_list.html

For more information on configuring VACLs on CatOS 8.x software versions, please consult the following link:

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/catos/8.x/configuration/guide/acc_list.html

Cisco ASA and Cisco PIX Software

Cisco ASA and Cisco PIX Software provide a method to expire stalled half-closed TCP connections that helps mitigate against the TCP state manipulation vulnerabilities. This method protects against attacks directed to a firewall and devices protected by a firewall. The timeout half-closed command will expire TCP sessions that have remained in a half-closed state beyond a user-configured timeout.

FIREWALL(config)# timeout half-closed 0:5:0

This command will set the TCP half-closed timeout to the smallest permitted value of five minutes. For more information on the TCP half-closed timeout, please consult the following link:

http://www.cisco.com/en/US/docs/security/asa/asa80/command/reference/t.html#wp1500148

Cisco Nexus Software

Cisco Nexus software provides several ACL methods to mitigate against the TCP state manipulation vulnerabilities. For more information on configuring ACLs on Nexus 5000 systems, please consult the following link:

http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/configuration/guide/cli_rel_4_0_1a/sec_ipacls.html

For more information on configuring ACLs on Nexus 7000 systems, please consult the following link:

http://www.cisco.com/en/US/docs/switches/datacenter/sw/4_1/nx-os/security/configuration/guide/sec_nx-os-cfg.html

Cisco Applied Mitigation Bulletin

Additional mitigations that can be deployed on Cisco devices within the network are available in the Cisco Applied Mitigation Bulletin companion document for this advisory, which is available at the following link:

http://tools.cisco.com/security/center/content/CiscoAppliedMitigationBulletin/cisco-amb-20090908-tcp24

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 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.

The TCP state manipulation vulnerability was coordinated by CERT-FI based on research referenced in their public advisory. To view their advisory and credited references, please refer to:

https://www.cert.fi/haavoittuvuudet/2008/tcp-vulnerabilities.html leavingcisco.com

The TCP proof-of-concept tool, known as Sockstress, was provided to Cisco by Robert E. Lee and Jack Louis of Outpost24. The Cisco Nexus vulnerability was discovered by Cisco.

Status of This Notice: Final

This information is Cisco Highly Confidential - Do not redistribute.

THIS IS A DRAFT VERSION OF A SECURITY NOTICE THAT CONTAINS UNRELEASED INFORMATION ABOUT CISCO PRODUCTS. DISTRIBUTION WITHIN CISCO IS LIMITED TO PERSONNEL WITH A NEED TO KNOW. THIS DRAFT MAY CONTAIN ERRORS OR OMIT IMPORTANT INFORMATION.

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


Distribution

This advisory is posted on Cisco's worldwide website at:

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090908-tcp24

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-teams@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 1.3

2009-September-28

Added to Products Confirmed Not Vulnerable list; updated software table.

Revision 1.2

2009-September-16

Revised the Affected Products section for Linksys products and the Exploitation and Public Announcements section

Revision 1.1

2009-September-11

Updated vulnerable software

Revision 1.0

2009-September-08

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.


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