[nsp] Cisco Security Advisory: Cisco IPSec VPN Services Module Malformed IKE Packet Vulnerability

Thu Apr 8 13:11:56 EDT 2004

   The Cisco IP Security (IPSec) VPN Services Module (VPNSM) is a high-speed
   module for the Cisco Catalyst 6500 Series Switch and the Cisco 7600 Series
   Internet Router that provides infrastructure-integrated IPSec VPN
   services.

   A malformed Internet Key Exchange (IKE) packet may cause the Cisco
   Catalyst 6500 Series Switch or the Cisco 7600 Series Internet Router
   hardware, with the VPNSM installed, to crash and reload.

   This vulnerability is documented as Cisco bug ID CSCed30113. There is no
   workaround available to mitigate the effects of this vulnerability. Cisco
   is providing fixed software at no charge, and recommends that customers
   upgrade to it.

   This advisory will be posted at
   http://www.cisco.com/warp/public/707/cisco-sa-20040408-vpnsm.shtml.

Affected Products

  Vulnerable Products

   All Cisco Catalyst 6500 Series Switch and the Cisco 7600 Series Internet
   Router hardware, with the VPNSM installed, running the following Cisco IOS
   releases are affected by this vulnerability:

   +------------------------------------------+
   | Release Train |    Affected Releases     |
   |---------------+--------------------------|
   |12.2SXA        |earlier than 12.2(17b)SXA |
   |---------------+--------------------------|
   |12.2SXB        |earlier than 12.2(17d)SXB |
   |---------------+--------------------------|
   |12.2SY         |earlier than 12.2(14)SY03 |
   |---------------+--------------------------|
   |12.2ZA         |earlier than 12.2(14)ZA8  |
   +------------------------------------------+

  Products Confirmed Not Vulnerable

   Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Internet Router
   hardware, using the VPNSM and running Cisco IOS release train 12.1E are
   not affected by this vulnerability.

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

   To determine your software revision, type show version at the command line
   prompt.

Details

   A malformed IKE packet may cause the Cisco Catalyst 6500 Series Switch or
   the Cisco 7600 Series Internet Router hardware, with the VPNSM installed,
   to crash and reload.

   This vulnerability could be used to conduct a Denial of Service (DoS)
   attack on the Cisco Catalyst 6500 Series Switch or the Cisco 7600 Series
   Internet Router hardware platforms that have the VPNSM installed in them.
   This vulnerability is known to only exist in the modified IKE code which
   was incorporated in the 12.2SXA, 12.2SXB, 12.2SY, and 12.2ZA Cisco IOS
   software release trains.

   More information on the VPNSM is available at
   http://www.cisco.com/en/US/products/hw/modules/ps2706/products_data_sheet09186a00800c4fe2.html.

   The Internetworking Terms and Cisco Systems Acronyms online guides can be
   found at http://www.cisco.com/univercd/cc/td/doc/cisintwk/.

   This vulnerability is documented in the Cisco Bug Toolkit as Bug ID
   CSCed30113 (registered customers only) .

Impact

   This vulnerability could be used to conduct a Denial of Service (DoS)
   attack on the Cisco Catalyst 6500 Series Switch or the Cisco 7600 Series
   Internet Router hardware platforms that have the VPNSM installed in them.

Software Versions and Fixes

   This vulnerability has been fixed in the following Cisco IOS releases for
   the Cisco Catalyst 6500 Series Switch and the Cisco 7600 Series Internet
   Router hardware:

   +------------------------------------------+
   |Release Train|       Fixed Releases       |
   |-------------+----------------------------|
   |12.2SXA      |12.2(17b)SXA and later      |
   |-------------+----------------------------|
   |12.2SXB      |12.2(17d)SXB and later      |
   |-------------+----------------------------|
   |12.2SY       |12.2(14)SY03 and later      |
   |-------------+----------------------------|
   |             |12.2(14)ZA8 and later. No   |
   |12.2ZA       |software availability date  |
   |             |has been determined yet.    |
   +------------------------------------------+

   Please refer to these documents for more information:

     * 12.2(17b)SXA Release Notes:
       http://www.cisco.com/en/US/products/sw/iosswrel/ps5014/prod_bulletin09186a00801df1dd.html
     * 12.2(17d)SXB Release Notes:
       http://www.cisco.com/en/US/products/sw/iosswrel/ps5012/prod_bulletin09186a00802078b5.html
     * 12.2(14)SY03 Release Notes:
       http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_tech_note09186a00801ab5a3.shtml

Obtaining Fixed Software

   Cisco is offering free software upgrades to address this vulnerability for
   all affected customers.

  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/tacpage/library/12.2/index.shtml.

  Customers using Third-party Support Organizations

   Customers whose Cisco products are provided or maintained through prior or
   existing agreement with third-party support organizations such as Cisco
   Partners, authorized resellers, or service providers should contact that
   support organization for assistance with the upgrade, which should be free
   of charge.

  Customers without Service Contracts

   Customers who purchase direct from Cisco but who do not hold a Cisco
   service contract and customers who purchase through third-party vendors
   but are unsuccessful at obtaining fixed software through their point of
   sale should get their upgrades by contacting the Cisco Technical
   Assistance Center (TAC). TAC contacts are as follows.

     * +1 800 553 2447 (toll free from within North America)
     * +1 408 526 7209 (toll call from anywhere in the world)
     * e-mail: tac at cisco.com

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

   Please do not contact either "psirt at cisco.com" or
   "security-alert at cisco.com" for software upgrades.

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

   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/public/sw-license-agreement.html, or as otherwise set
   forth at Cisco.com Downloads at
   http://www.cisco.com/public/sw-center/sw-usingswc.shtml.

Workarounds

   There is no workaround for this vulnerability. The Cisco PSIRT recommends
   that affected users upgrade to a fixed software version of code.

   As a possible mitigation, users deploying the VPNSM for site to site
   connectivity could apply ACLs on the Cisco Catalyst 6500 Series Switch or
   the Cisco 7600 Series Internet Router to limit the IP addresses that can
   establish IPSec sessions with the VPNSM.

Exploitation and Public Announcements

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

   This vulnerability was reported to Cisco PSIRT by a customer.

Status of This Notice: FINAL

   This is a final advisory. Although Cisco cannot guarantee the accuracy of
   all statements in this advisory, all of the facts have been checked to the
   best of our ability. Cisco does not anticipate issuing updated versions of
   this advisory unless there is some material change in the facts. Should
   there be a significant change in the facts, Cisco may update this
   advisory.

   Note:  A stand-alone copy or paraphrase of the text of this security
   advisory 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 will be posted on Cisco's worldwide website at
   http://www.cisco.com/warp/public/707/cisco-sa-20040408-vpnsm.shtml.

   In addition to worldwide web posting, a text version of this notice is
   clear-signed with the Cisco PSIRT PGP key having the fingerprint 8C82 5207
   0CA9 ED40 1DD2 EE2A 7B31 A8CF 32B6 B590 and is posted to the following
   e-mail and Usenet news recipients.

     * cust-security-announce at cisco.com
     * first-teams at first.org (includes CERT/CC)
     * bugtraq at securityfocus.com
     * vulnwatch at vulnwatch.org
     * cisco at spot.colorado.edu
     * cisco-nsp at puck.nether.net
     * full-disclosure at lists.netsys.com
     * comp.dcom.sys.cisco at newsgate.cisco.com
     * Various internal Cisco mailing lists

   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 1.0|2004-April-8|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/warp/public/707/sec_incident_response.shtml. This
   includes instructions for press inquiries regarding Cisco security
   notices. All Cisco security advisories are available at
   http://www.cisco.com/go/psirt.

     ----------------------------------------------------------------------
-----BEGIN PGP SIGNATURE-----
Comment: PGP Signed by Sharad Ahlawat, Cisco Systems PSIRT

iD8DBQFAdXhqezGozzK2tZARAthDAJ965nB3NbQIe0AeReU1eujRTP3hFQCcD/Xw
Q5FyVmG1rKUMcr2CBjWj6SE=
=YSsT
-----END PGP SIGNATURE-----