Summary

• A vulnerability in Cisco TelePresence Server devices running software versions 3.0 through 4.2(4.18) could allow an unauthenticated, remote attacker to cause a kernel panic on the device.
  
  The vulnerability exists due to a failure to properly handle a specially crafted stream of IPv6 packets. A successful exploit could allow an attacker to cause a kernel panic, rebooting the device.
  
  Cisco has released software updates that address this vulnerability. Workarounds that mitigate this vulnerability are available.
  
  This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160406-cts

Affected Products

• Vulnerable Products

  The following Cisco TelePresence Server device running Cisco TelePresence Server software versions 3.0 to 4.2(4.18) are vulnerable:
  

  • Cisco TelePresence Server Mobility Services Engine (MSE) 8710

  Products Confirmed Not Vulnerable

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

Workarounds

• Customers that do not use IPv6 for teleconferencing can disable IPv6 as a workaround until the system can be updated.
  
  Customers can disable IPv6 calling with the following commands:
  

  Network > Network Settings > IP Configuration
  
  Disable IPv6 on the port.
  
  Note: You can disable IPv6 on the TelePresence Server port, but only if logged in using IPv4.
  
  When finished, click Update IP Configuration.

Fixed Software

• Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license: http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
  
  Additionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.
  
  When considering software upgrades, customers are advised to consult the Cisco Security Advisories and Responses archive at http://www.cisco.com/go/psirt and review subsequent advisories to determine exposure and a complete upgrade solution.
  
  In all cases, customers should ensure that the devices to upgrade contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
  
  Customers Without Service Contracts
  
  Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco Technical Assistance Center (TAC): http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html
  
  Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.
  
  Fixed Releases
  

  Customers should upgrade to an appropriate release as indicated in the applicable table in this section. To help ensure a complete upgrade solution, consider that this advisory is part of a collection that includes the following advisories:

  • cisco-sa-20160406-cts: Cisco TelePresence Server Crafted IPv6 Packet Handling Denial of Service Vulnerability
  • cisco-sa-20160406-cts1: Cisco TelePresence Server Crafted URL Handling Denial of Service Vulnerability
  • cisco-sa-20160406-cts2: Cisco TelePresence Server Malformed STUN Packet Processing Denial of Service Vulnerability

  In the following table, the left column lists major releases of Cisco software. The center column indicates whether a major release is affected by the vulnerability described in this advisory and the first minor release that includes the fix for this vulnerability. The right column indicates whether a major release is affected by all the vulnerabilities described in this collection of advisories and which release includes fixes for those vulnerabilities.

  
  
  

  Cisco TelePresence Server Product	First Fixed Release for This Vulnerability	First Fixed Release for This Vulnerability and All Vulnerabilities Described in the Collection of Advisories
  Cisco TelePresence Server Crafted IPv6 Packet Handling Denial of Service Vulnerability
  8710	4.2(4.23)	4.2(4.23)
  Cisco TelePresence Server Crafted URL Handling Denial of Service Vulnerability
  7010/8710/310/320/VM	4.2(4.18)	4.2(4.23)
  820	4.2(3.72)	4.2(3.72)
  Cisco TelePresence Server Malformed STUN Packet Denial of Service Vulnerability
  7010/8710/310/320/VM	4.2(4.18)	4.2(4.23)

Exploitation and Public Announcements

• The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

Source

• This vulnerability was found during internal testing.

URL

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160406-cts

Revision History

• Version	Description	Section	Status	Date
  1.0	Initial public release.	-	Final	2016-April-06

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