Cisco Catalyst 4500E Series Switch with Cisco Catalyst Supervisor Engine 7L-E Denial of Service Vulnerability

Summary

• The Catalyst 4500E series switch with Supervisor Engine 7L-E contains a denial of service (DoS) vulnerability when processing specially crafted packets that can cause a reload of the device.
  
  Cisco has released software updates that address this vulnerability.
  
  Workarounds that mitigate this vulnerability are not available.
  
  This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20120926-ecc
  

  Note: The September 26, 2012, Cisco IOS Software Security Advisory bundled publication includes nine Cisco Security Advisories. Eight of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses a vulnerability in Cisco Unified Communications Manager. Each Cisco IOS Software Security Advisory lists the Cisco IOS Software releases that correct the vulnerability or vulnerabilities detailed in the advisory as well as the Cisco IOS Software releases that correct all Cisco IOS Software vulnerabilities in the September 2012 bundled publication.

  Individual publication links are in "Cisco Event Response: Semi-Annual Cisco IOS Software Security Advisory Bundled Publication" at the following link:

  http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_sep12.html

  
  

Affected Products

• This vulnerability affects only the Catalyst 4500E series switch with Supervisor Engine 7L-E running Cisco IOS XE Software Release 03.02.00.XO.15.0(2)XO. The device is vulnerable when running an affected version of Cisco IOS XE Software, regardless of the configuration of the device
  
  To identify the hardware type log into the device and issue the show module Cisco IOS XE Software CLI command. The following example shows a Catalyst 4500-E Series with a Catalyst Supervisor Engine 7L-E installed:
  

  switch#show module
  Chassis Type : WS-C4507R+E
  
  Power consumed by backplane : 40 Watts
  
  Mod Ports Card Type                              Model              Serial No.
  ---+-----+--------------------------------------+------------------+-----------
   4     6  Sup 7L-E 10GE (SFP+), 1000BaseX (SFP)  WS-X45-SUP7L-E     CAT1532L4ZA
   5    48  10/100/1000BaseT (RJ45)                WS-X4448-GB-RJ45   JAB023456A3
  

  To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the show version command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the show version command or may provide different output.
  
  The following example identifies a Catalyst 4500E series switch with Supervisor Engine 7L-E that is running Cisco IOS XE Software Release 03.02.00.XO.15.0(2)XO with an installed image name of cat4500e-universal.SPA:
  

  Catalyst_4500#show version
  Cisco IOS Software, IOS-XE Software, Catalyst 4500 L3 Switch Software (cat4500e-UNIVERSAL-M), Version 03.02.00.XO RELEASE SOFTWARE (fc2)
  Technical Support: http://www.cisco.com/techsupport
  Copyright (c) 1986-2011 by Cisco Systems, Inc.
  Compiled Thu 22-Sep-11 19:53 by prod_rel_team
  
  
  <--- section removed for brevity ---> 
  
  System returned to ROM by reload
  System image file is "bootflash:/cat4500e-universal.SPA.03.02.00.XO.150-2.XO.bin"
  Last reload reason: Reload command
  
  
  License Information for 'WS-X45-SUP7L-E'
      License Level: lanbase   Type: Default. No valid license found.
      Next reboot license Level: lanbase
  
  

       <--- section removed for brevity --->

  Additional information about Cisco IOS Software release naming conventions is available in White Paper: Cisco IOS and NX-OS Software Reference Guide.
  

  Vulnerable Products

  The following products are affected by this vulnerability, when running Cisco IOS XE Software Release 03.02.00.XO.15.0(2)XO:
  

  • Catalyst 4500E series switch with Supervisor Engine 7L-E

  Products Confirmed Not Vulnerable

  The following products are not affected by this vulnerability:
  

  • Cisco Catalyst Supervisor Engine II
  • Cisco Catalyst Supervisor Engine IV
  • Cisco Catalyst Supervisor Engine V
  • Cisco Catalyst Supervisor Engine 6-E and 6-LE
  • Cisco Catalyst Supervisor Engine 7-E
  • Cisco Catalyst 4500-X Series Switches
  • Cisco Catalyst 4900 Series Switches
  • Cisco ME 4924-10GE Ethernet Aggregation Switch

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

Details

• Cisco Catalyst 4500E series switches with Supervisor Engine 7L-E contain a denial of service (DoS) vulnerability that could allow an unauthenticated, remote attacker to cause the device supervisor card to reload.
  
  The vulnerability is due to improper processing of malformed network packets. An unauthenticated, remote attacker could exploit this vulnerability by sending specially crafted packets to or through the affected device. An exploit could allow the attacker to reload the affected device supervisor card, resulting in a DoS condition.
  When the specially crafted packets are received the device will indicate an error message about an uncorrected error-correcting code (ECC) failure. The following is an example of this error message:
  
  %C4K_SWITCHINGENGINEMAN-4-VFEL2INTERRUPT: (Suppressed 9 times)VFE L2 sptMemory interrupt. valid: 1 addr: 0x0 data: 0x0 uncorrected ecc: 0
  IF 100 of these packets have been received in a period of less than 72 hours, the device will reload.
  
  There are also packets that would cause a similar error message but result in a corrected ECC error message. These are informational and do not have an impact on the device itself. The following is an example of this error message:
  
  %C4K_SWITCHINGENGINEMAN-4-VFEL2INTERRUPT: VFE L2 sptMemory interrupt. valid: 1 addr: 0x0 data: 0x0 corrected ecc: 2
  
  The device is vulnerable when running Cisco IOS XE Software Release 03.02.00.XO.15.0(2)XO, regardless of the configuration of the device.
  
  This vulnerability has been documented in Cisco Bug ID CSCty88456 (registered customers only) and has been assigned the Common Vulnerabilities and Exposures (CVE) ID CVE-2012-4622.
  

  
  

  
  

Workarounds

• The are no workarounds for this vulnerability. The use of port access control lists (PACL) and VLAN access control lists (VACL) does not mitigate this vulnerability.

Fixed Software

• 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 be upgraded 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.

  Cisco IOS Software

  Cisco IOS Software is not affected by the vulnerability that is disclosed in this advisory.

  Cisco IOS XE Software

  This vulnerability affects Cisco IOS XE Software Release 03.02.00.XO.15.0(2)XO only.
  
  Devices running the affected Cisco IOS XE Software Release should migrate to release 3.3.0.SG or later.
  
  

  Cisco IOS XE Software Release	First Fixed Release	First Fixed Release for All Advisories in the September 2012 Cisco IOS Software Security Advisory Bundled Publication
  2.1.x	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  2.2.x	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  2.3.x	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  2.4.x	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  2.5.x	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  2.6.x	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  3.1.xS	Not vulnerable	3.1.4S
  3.1.xSG	Not vulnerable	Vulnerable; migrate to 3.2.5SG or later.
  3.2.xS	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  3.2.xSG	Not vulnerable	3.2.5SG
  3.2.xXO	Vulnerable; migrate to 3.3.0SG or later.	Vulnerable; migrate to 3.3.1SG or later.
  3.3.xS	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  3.3.x.SG	Not vulnerable	3.3.1SG
  3.4.xS	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  3.5.xS	Not vulnerable	Vulnerable; migrate to 3.6.0S or later.
  3.6.xS	Not vulnerable	Not vulnerable
  3.7.xS	Not vulnerable	Not vulnerable

  
  For a mapping of Cisco IOS XE Software releases to Cisco IOS Software releases, refer to Cisco IOS XE 2 Release Notes, Cisco IOS XE 3S Release Notes, and Cisco IOS XE 3SG Release Notes.
  

  Cisco IOS XR Software

  Cisco IOS XR Software is not affected by the vulnerability that is disclosed in this advisory.

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.

  This vulnerability was discovered when handling customer service requests.

URL

• http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20120926-ecc

Revision History

• Revision 1.0

  2012-September-26

  Initial public release

  Show Less