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Cisco Security Advisory

Cisco IOS Software Layer 2 Tunneling Protocol (L2TP) Denial of Service Vulnerability

Advisory ID: cisco-sa-20080924-l2tp

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20080924-l2tp

Revision 1.1

For Public Release 2008 September 24 16:00  UTC (GMT)


Summary

A vulnerability exists in the Cisco IOS software implementation of Layer 2 Tunneling Protocol (L2TP), which affects limited Cisco IOS software releases.

Several features enable the L2TP mgmt daemon process within Cisco IOS software, including but not limited to Layer 2 virtual private networks (L2VPN), Layer 2 Tunnel Protocol Version 3 (L2TPv3), Stack Group Bidding Protocol (SGBP) and Cisco Virtual Private Dial-Up Networks (VPDN). Once this process is enabled the device is vulnerable.

This vulnerability will result in a reload of the device when processing a specially crafted L2TP packet.

Cisco has released free software updates that address this vulnerability.

Workarounds that mitigate this vulnerability are available.

This advisory is posted at http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20080924-l2tp.

Note: The September 24, 2008 IOS Advisory bundled publication includes twelve Security Advisories. Eleven of the advisories address vulnerabilities in Cisco's IOS software, and one advisory addresses vulnerabilities in Cisco Unified Communications Manager. Each Advisory lists the releases that correct the vulnerability described in the Advisory.

Individual publication links are listed below:

Affected Products

All devices running affected versions of 12.2 or 12.4 Cisco IOS system software and that have a vulnerable configuration are affected by this vulnerability.

Vulnerable Products

To determine if a device is vulnerable, first confirm that the device is running an affected version of 12.2 or 12.4 Cisco IOS system software. Then check for the process L2TP mgmt daemon running on the device.

To determine the software version running on a Cisco product, log in to the device and issue the show version command to display the system banner. Cisco IOS software will identify itself as "Internetwork Operating System Software" or simply "IOS." On the next line of output, the image name will be displayed between parentheses, followed by "Version" and the IOS release name. Other Cisco devices will not have the show version command or will give different output.

The following example identifies a Cisco product that is running Cisco IOS Software Release 12.4(11)T2:

Router#show version
Cisco IOS Software, 7200 Software (C7200-ADVSECURITYK9-M), Version 12.4(11)T2, RELEASE SOFTWARE (fc4)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2007 by Cisco Systems, Inc.
Compiled Tue 01-May-07 04:19 by prod_rel_team


<output truncated>

Additional information on the Cisco IOS release naming conventions can be found in the document entitled "White Paper: Cisco IOS Reference Guide," which is available at http://www.cisco.com/warp/public/620/1.html

To check if the process L2TP mgmt daemon is running on a device, log into the command line interface (CLI) and issue the command show processes | include L2TP . (NOTE: The command is case sensitive.) If the output returns a line with the process name L2TP mgmt daemon, the device is vulnerable. The following example shows a device running the L2TP mgmt daemon process:

Router#show processes | include L2TP
 158 Mwe 62590FE4            4          3    133322900/24000  0 L2TP mgmt daemon
Router#

The L2TP mgmt daemon is started by several different types of configurations that may be deployed in networks that leverage the L2TP protocol. If any of the following commands appear within a device's configuration, show running-config, then the device will have started the L2TP mgmt daemon and is vulnerable.

  • Device is configured with Virtual Private Dial-Up Networks (VPDN).
    The command vpdn enable will appear in the device configuration.
  • Device is configured for L2TP or L2TPv3 Client-Initiated VPDN Tunneling.
    The command pseudowire peer-ip-address vcid pw-class pw-class-name " appears in the device configuration.
  • Device is configured with Stack Group Bidding Protocol (SGBP).
    The command sgbp group group-name will appear in the device configuration.
  • A L2TP signaling template has been defined.
    The command l2tp-class l2tp-class name will appear in the device configuration.
  • Devices configured for Layer 2 Tunnel Protocol Version 3
    The commands pseudowire-class pseudowire-class name and a successfully applied interface xconnect command will appear in the device configuration.

Products Confirmed Not Vulnerable

  • Devices that are running Cisco IOS versions that are not explicitly listed in the software table below as vulnerable, are not affected.
  • Cisco IOS XR is not affected.
  • Cisco IOS XE is not affected.

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

Details

Documented in RFC2661, L2TP and RFC3931, L2TPv3 are protocols for tunneling network traffic between two peers over an existing network.

A device running affected 12.2 and 12.4 versions of Cisco IOS and that has the L2TP mgmt daemon process running will reload when processing a specially crafted L2TP packet.

Several features leverage the L2TP protocol and start the L2TP mgmt daemon within Cisco IOS. These features have been outlined in this advisory under the Vulnerable Products section.

This vulnerability is documented in Cisco bug ID CSCsh48879 ( registered customers only) and Common Vulnerabilities and Exposures (CVE) identifier CVE-2008-3813 has been assigned to this vulnerability.

Vulnerability Scoring Details

Cisco has provided scores for the vulnerability 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.

CSCsh48879 ( registered customers only) - Crafted L2TP packet triggers a device reload.

Calculate the environmental score of CSCsh48879

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 will result in a reload of the device. Repeated exploitation may result in an extended denial of service (DoS) condition.

Software Versions and Fixes

When considering software upgrades, also consult http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution.

In all cases, customers should exercise caution to be certain the devices to be upgraded contain sufficient memory and that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider for assistance.

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

Major Release

Availability of Repaired Releases

Affected 12.0-Based Releases

First Fixed Release

Recommended Release

There are no affected 12.0 based releases

Affected 12.1-Based Releases

First Fixed Release

Recommended Release

There are no affected 12.1 based releases

Affected 12.2-Based Releases

First Fixed Release

Recommended Release

12.2

Not Vulnerable

 

12.2B

Not Vulnerable

 

12.2BC

Not Vulnerable

 

12.2BW

Not Vulnerable

 

12.2BX

Not Vulnerable

 

12.2BY

Not Vulnerable

 

12.2BZ

Not Vulnerable

 

12.2CX

Not Vulnerable

 

12.2CY

Not Vulnerable

 

12.2CZ

Not Vulnerable

 

12.2DA

Not Vulnerable

 

12.2DD

Not Vulnerable

 

12.2DX

Not Vulnerable

 

12.2EW

Not Vulnerable

 

12.2EWA

Not Vulnerable

 

12.2EX

Not Vulnerable

 

12.2EY

Not Vulnerable

 

12.2EZ

Not Vulnerable

 

12.2FX

Not Vulnerable

 

12.2FY

Not Vulnerable

 

12.2FZ

Not Vulnerable

 

12.2IRB

Not Vulnerable

 

12.2IXA

Not Vulnerable

 

12.2IXB

Not Vulnerable

 

12.2IXC

Not Vulnerable

 

12.2IXD

Not Vulnerable

 

12.2IXE

Not Vulnerable

 

12.2IXF

Not Vulnerable

 

12.2IXG

Not Vulnerable

 

12.2JA

Not Vulnerable

 

12.2JK

Not Vulnerable

 

12.2MB

Not Vulnerable

 

12.2MC

Not Vulnerable

 

12.2S

Not Vulnerable

 

12.2SB

Not Vulnerable

 

12.2SBC

Not Vulnerable

 

12.2SCA

Not Vulnerable

 

12.2SE

Note: Releases prior to 12.2(37)SE are not vulnerable. First fixed in 12.2(44)SE

12.2(46)SE

12.2SEA

Not Vulnerable

 

12.2SEB

Not Vulnerable

 

12.2SEC

Not Vulnerable

 

12.2SED

Not Vulnerable

 

12.2SEE

Not Vulnerable

 

12.2SEF

Not Vulnerable

 

12.2SEG

Not Vulnerable

 

12.2SG

Note: Releases prior to 12.2(37)SG are not vulnerable. First Fixed in 12.2(44)SG

12.2(46)SG1

12.2SGA

Not Vulnerable

 

12.2SL

Not Vulnerable

 

12.2SM

Not Vulnerable

 

12.2SO

Not Vulnerable

 

12.2SRA

Not Vulnerable

 

12.2SRB

12.2(33)SRB1

12.2(33)SRB4

12.2SRC

Not Vulnerable

 

12.2SU

Not Vulnerable

 

12.2SV

Not Vulnerable

 

12.2SVA

Not Vulnerable

 

12.2SVC

Not Vulnerable

 

12.2SVD

Not Vulnerable

 

12.2SW

Not Vulnerable

 

12.2SX

Not Vulnerable

 

12.2SXA

Not Vulnerable

 

12.2SXB

Not Vulnerable

 

12.2SXD

Not Vulnerable

 

12.2SXE

Not Vulnerable

 

12.2SXF

Not Vulnerable

 

12.2SXH

Not Vulnerable

 

12.2SY

Not Vulnerable

 

12.2SZ

Not Vulnerable

 

12.2T

Not Vulnerable

 

12.2TPC

Not Vulnerable

 

12.2XA

Not Vulnerable

 

12.2XB

Not Vulnerable

 

12.2XC

Not Vulnerable

 

12.2XD

Not Vulnerable

 

12.2XE

Not Vulnerable

 

12.2XF

Not Vulnerable

 

12.2XG

Not Vulnerable

 

12.2XH

Not Vulnerable

 

12.2XI

Not Vulnerable

 

12.2XJ

Not Vulnerable

 

12.2XK

Not Vulnerable

 

12.2XL

Not Vulnerable

 

12.2XM

Not Vulnerable

 

12.2XN

Not Vulnerable

 

12.2XNA

Not Vulnerable

 

12.2XNB

Not Vulnerable

 

12.2XO

Not Vulnerable

 

12.2XQ

Not Vulnerable

 

12.2XR

Not Vulnerable

 

12.2XS

Not Vulnerable

 

12.2XT

Not Vulnerable

 

12.2XU

Not Vulnerable

 

12.2XV

Not Vulnerable

 

12.2XW

Not Vulnerable

 

12.2YA

Not Vulnerable

 

12.2YB

Not Vulnerable

 

12.2YC

Not Vulnerable

 

12.2YD

Not Vulnerable

 

12.2YE

Not Vulnerable

 

12.2YF

Not Vulnerable

 

12.2YG

Not Vulnerable

 

12.2YH

Not Vulnerable

 

12.2YJ

Not Vulnerable

 

12.2YK

Not Vulnerable

 

12.2YL

Not Vulnerable

 

12.2YM

Not Vulnerable

 

12.2YN

Not Vulnerable

 

12.2YO

Not Vulnerable

 

12.2YP

Not Vulnerable

 

12.2YQ

Not Vulnerable

 

12.2YR

Not Vulnerable

 

12.2YS

Not Vulnerable

 

12.2YT

Not Vulnerable

 

12.2YU

Not Vulnerable

 

12.2YV

Not Vulnerable

 

12.2YW

Not Vulnerable

 

12.2YX

Not Vulnerable

 

12.2YY

Not Vulnerable

 

12.2YZ

Not Vulnerable

 

12.2ZA

Not Vulnerable

 

12.2ZB

Not Vulnerable

 

12.2ZC

Not Vulnerable

 

12.2ZD

Not Vulnerable

 

12.2ZE

Not Vulnerable

 

12.2ZF

Not Vulnerable

 

12.2ZG

Not Vulnerable

 

12.2ZH

Not Vulnerable

 

12.2ZJ

Not Vulnerable

 

12.2ZL

Not Vulnerable

 

12.2ZP

Not Vulnerable

 

12.2ZU

Not Vulnerable

 

12.2ZX

Not Vulnerable

 

12.2ZY

Not Vulnerable

 

12.2ZYA

Not Vulnerable

 

Affected 12.3-Based Releases

First Fixed Release

Recommended Release

There are no affected 12.3 based releases

Affected 12.4-Based Releases

First Fixed Release

Recommended Release

12.4

Not Vulnerable

 

12.4JA

Not Vulnerable

 

12.4JK

Not Vulnerable

 

12.4JL

Not Vulnerable

 

12.4JMA

Not Vulnerable

 

12.4JMB

Not Vulnerable

 

12.4JMC

Not Vulnerable

 

12.4JX

Not Vulnerable

 

12.4MD

Not Vulnerable

 

12.4MR

Note: Releases prior to 12.4(11)MR are not vulnerable. First fixed in 12.4(16)MR

12.4(19)MR

12.4SW

12.4(11)SW3

12.4(15)SW2; Available on 28-SEP-08

12.4T

Note: Releases prior to 12.4(11)T are not vulnerable. First fixed in 12.4(15)T

12.4(15)T7

12.4XA

Not Vulnerable

 

12.4XB

Not Vulnerable

 

12.4XC

Not Vulnerable

 

12.4XD

Not Vulnerable

 

12.4XE

Not Vulnerable

 

12.4XF

Not Vulnerable

 

12.4XG

Not Vulnerable

 

12.4XJ

Vulnerable; first fixed in 12.4T

12.4(15)T7

12.4XK

Not Vulnerable

 

12.4XL

Not Vulnerable

 

12.4XM

Not Vulnerable

 

12.4XN

Not Vulnerable

 

12.4XP

Not Vulnerable

 

12.4XQ

Not Vulnerable

 

12.4XT

Not Vulnerable

 

12.4XV

Vulnerable; contact TAC

 

12.4XW

12.4(11)XW1

12.4(11)XW9

12.4XY

Not Vulnerable

 

12.4XZ

Not Vulnerable

 

12.4YA

Not Vulnerable

 


Workarounds

The following workarounds have been identified for this vulnerability.

Note:  L2TP implementations will need to allow UDP 1701, from trusted addresses to infrastructure addresses. This does not provide for a full mitigation as the source addresses may be spoofed.

Note:  L2TPv3 over IP only implementations need to deny all UDP 1701 from anywhere to the infrastructure addresses.

  • Infrastructure Access Control Lists
    Although it is often difficult to block traffic that transits a network, it is possible to identify traffic that should never be allowed to target infrastructure devices and block that traffic at the border of networks. Infrastructure Access Control Lists (iACLs) are a network security best practice and should be considered as a long-term addition to good network security as well as a workaround for these specific vulnerabilities. The iACL example below should be included as part of the deployed infrastructure access-list which will protect all devices with IP addresses in the infrastructure IP address range:
    
    !--- Permit L2TP UDP 1701 packets from all trusted
    !--- sources destined to infrastructure addresses.
    !--- NOTE: This does not prevent spoofed attacks.
    !---           To be a full mitigation, no trusted source
    !---           addresses should be listed.
    !---           Omit this line if using a L2TPv3 over IP implementation only.
    
    
    access-list 150 permit udp TRUSTED_SOURCE_ADDRESSES MASK  
       INFRASTRUCTURE_ADDRESSES MASK eq 1701
    
    
    !--- Deny L2TP UDP 1701 packets from all
    !--- sources destined to infrastructure addresses.
    
    
    access-list 150 deny udp any INFRASTRUCTURE_ADDRESSES MASK eq 1701
    
    
    !--- If using a L2TPv3 over IP implementation ensure to allow L2TPv3
    
    
    access-list 150 permit 115 <source_ip_address and mask> 
       <destination_ip_address and mask>
    
    
    !--- Permit/deny all other Layer 3 and Layer 4 traffic in accordance
    !--- with existing security policies and configurations
    !--- Permit all other traffic to transit the device.
    
    
    access-list 150 permit ip any any
    
    
    !--- Apply access-list to all interfaces (only one example shown)
    
    
    interface serial 2/0
    ip access-group 150 in
    The white paper entitled "Protecting Your Core: Infrastructure Protection Access Control Lists" presents guidelines and recommended deployment techniques for infrastructure protection access lists. This white paper can be obtained at the following link: http://www.cisco.com/en/US/tech/tk648/tk361/technologies_white_paper09186a00801a1a55.shtml

  • Control Plane Policing
    Control Plane Policing (CoPP) can be used to block L2TP access to the device. Cisco IOS software releases 12.0S, 12.2SX, 12.2S, 12.3T, 12.4, and 12.4T support the CoPP feature. CoPP can be configured on a device to protect the management and control planes and minimize the risk and effectiveness of direct infrastructure attacks by explicitly permitting only authorized traffic that is sent to infrastructure devices in accordance with existing security policies and configurations. The CoPP example below should be included as part of the deployed CoPP which will protect all devices with IP addresses in the infrastructure IP address range.
    
    !--- Deny all trusted source L2TP UDP traffic sent to all IP addresses
    !--- configured on all interfaces of the affected device so that it
    !--- will not be policed by the CoPP feature.
    
    !--- NOTE: This does not prevent spoofed attacks.
    !---           To be a full mitigation, no trusted source
    !---           addresses should be listed.
    !---           Omit this line if using an L2TPv3 over IP implementation only.
    
    
    access-list 111 deny udp TRUSTED_SOURCE_ADDRESSES MASK  
       INFRASTRUCTURE_ADDRESSES MASK eq 1701
    
    
    !--- Permit all L2TP UDP traffic sent to all IP addresses
    !--- configured on all interfaces of the affected device so that it
    !--- will be policed and dropped by the CoPP feature
    
    
    access-list 111 permit udp any INFRASTRUCTURE_ADDRESSES MASK eq 1701
    
    
    !--- If using an L2TPv3 over IP implementation ensure not to drop L2TPv3
    
    
    access-list 111 deny 115 <source_ip_address and mask> 
       <destination_ip_address and mask>  
    
    
    !--- 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-l2tp-class
    match access-group 111
    
    
    
    !--- Create a Policy-Map that will be applied to the
    !--- Control-Plane of the device.
    
    
    
    policy-map drop-l2tp-traffic
    class drop-l2tp-class
    drop
    
    
    
    !--- Apply the Policy-Map to the 
    !--- Control-Plane of the device
    
    
    control-plane
    
    service-policy input drop-l2tp-traffic
    In the above CoPP example, the access control list 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. Please note that the policy-map syntax is different in the 12.2S and 12.0S Cisco IOS trains:
    policy-map drop-l2tp-traffic
    class drop-l2tp-class
    police 32000 1500 1500 conform-action drop exceed-action drop
    Additional information on the configuration and use of the CoPP feature is available at the following link: http://www.cisco.com/web/about/security/intelligence/coppwp_gs.html

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: http://tools.cisco.com/security/center/content/CiscoAppliedMitigationBulletin/cisco-amb-20080924-l2tp.

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

Exploitation and Public Announcements

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

This vulnerability was found by Cisco through internal testing.

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-20080924-l2tp

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 1.1

2009-April-16

Removed references to the combined software table, as it is now outdated

Revision 1.0

2008-September-24

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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