Cisco Security Advisory

Cisco Security Agent Vulnerable to Privilege Escalation

Advisory ID: cisco-sa-20051129-csa

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20051129-csa

Revision 1.0

For Public Release 2005 November 29 16:00  UTC (GMT)


Summary

Cisco Security Agent (CSA) is a security software agent that provides threat protection for server and desktop computing systems. CSA agents can be managed by CiscoWorks VMS Management Center for Cisco Security Agents or can be standalone agents running on Cisco IP Communications application servers. Standalone agents for Cisco IP Communications application servers must be manually installed on the IP Communications application server.

A vulnerability exists in CSA agents that can allow a privilege escalation through locally executed software, providing a normal user or attacker with local system level privileges on a Windows workstation or server running managed or standalone CSA 4.5.0 or 4.5.1 agents.

Cisco has made free software available to address this vulnerability for affected customers.

This advisory is posted at http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20051129-csa

Affected Products

This section provides details on affected products.

Vulnerable Products

CSA 4.5.0 and 4.5.1 agents managed by CiscoWorks VMS Management Center for Cisco Security Agents and standalone agents running on Cisco IP Communications application servers are affected when running on:

  • Microsoft Windows platforms including:
    - Windows 2003
    - Windows 2000 Server and Advanced Server
    - Windows NT v4.0 Server and Enterprise Server (SP 6a)
    - Windows NT 4 Workstation (SP 6a)
    - Windows 2000 Professional
    - Windows XP Professional
  • Cisco CSA 4.5.0 (all builds) managed and standalone agents while running on Microsoft Windows
  • Cisco CSA 4.5.1 (all builds) managed and standalone agents while running on Microsoft Windows
  • Cisco CSA for CallManager versions 4.5.1 build 628 and 4.5.0 build 573.

    Note: These versions are used by CallManager, Cisco Conference Connection (CCC), Emergency Responder, IPCC Express, IP Interactive Voice Response (IP IVR), and IP Queue Manager

  • Cisco CSA for Intelligent Contact Management (ICM), IPCC Enterprise, and IPCC Hosted version 4.5.1 build 616
  • Cisco CSA for Cisco Voice Portal (CVP) 3.0 and 3.1 version 4.5.0 build 573.

    Note: This version is used by CVP 3.0 and 3.1 and CVP VXML Server.

Products Confirmed Not Vulnerable

The following products are confirmed not vulnerable:

  • Cisco CSA 4.0.3 (all builds) and earlier managed and standalone agents
  • Cisco CSA 4.0.2 (all builds) and earlier managed and standalone agents
  • Cisco CSA 4.0.1 (all builds) and earlier managed and standalone agents
  • Cisco CSA 3.x versions
  • Okena Stormwatch 3.x versions
  • Cisco CSA agents running on Solaris
  • Cisco CSA agents running on Linux

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

Determining the CSA Client Version

In order to determine which version of CSA is running on client machines, "right click" on the CSA icon in the Windows task bar. On the pop-up menu, selecting "About ..." will display the version number of the agent in a pop-up window containing text similar to "Cisco Security Agent V4.5 build 565."

Determining the CSA Client Version with the Management Console

You can also determine the CSA version using the Management Console for Cisco Security Agent on your CiscoWorks server. Complete these steps:

  1. Login at:
    http://ciscoworks-hostname:1741/
  2. Choose VPN/Security Managment Solution > Management Center > Security Agents, and then click the Security Agents tab.
    This launches the "Management Center for Cisco Security Agents."
  3. Within the browser window, locate the tab in the center marked "Help."
  4. Click the sub-item labeled "About." The version of the Cisco Security Agents appears in a pop-up window containing text similar to:
    Management Center for Cisco Security Agents V4.5-1 build 616.

Note: You can only manage CSA 4.5.X Agents with Version 4.5-X (any build) Management Center for Cisco Security Agents.

Details

Cisco Security Agent provides threat protection for server and desktop computing systems. Vulnerable versions of Cisco Security Agent may allow software executed locally to bypass systems protections and run with elevated privileges resulting in normal users and attackers obtaining local system level privileges.

Agent checks configured to prevent malicious software from running on a CSA protected system will be active; however, any checks that occur after successful exploitation may be bypassed.

This issue is not related to a Microsoft Operating System issue nor can a CSA policy modification change this behavior.

This vulnerability is documented in the Cisco Bug Toolkit as Bug ID CSCsc42373 ( registered customers only)

For information about local system level privileges, refer to:

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 .


Impact

Successful exploitation of the vulnerability may result in a normal user or attacker gaining full control of the system, including the disabling of the CSA agent.

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.

The fixed version of the Cisco Security Agent software requires no more resources than older 4.5.0 and 4.5.1 builds. It should be suitable for any system currently running 4.5.0 or 4.5.1.


Workarounds

Workarounds for Cisco CSA 4.5.0 and 4.51 Managed Agents Running on Microsoft Windows

  • The risk of this issue can be mitigated by controlling the software allowed to run on workstations and servers.
  • Disabling or uninstalling the CSA agent is a workaround for this particular issue but leaves the workstation or server at risk to all other issues that the agent provides protection against. Disabling or uninstalling the CSA agent should only be considered as a last resort
  • There are no additional workarounds for this vulnerability. Please refer to the Obtaining Fixed Software section for appropriate solutions to resolve this vulnerability

Mitigation and Best Practices for Cisco CallManager and Voice Application Servers

  • The risk of this issue can be mitigated by controlling the software allowed to run on the server. Cisco strongly recommends configuring and using only the software that is approved to be installed on Cisco CallManager and Voice Application Servers.
  • IP telephony network security best practices can provide additional mitigation.
  • Cisco CallManagers and Voice Application servers should be on their own, separate IP networks
  • Cisco CallManagers and Voice Application servers should be protected at layer 2.
  • Access controls should be employed to protect voice networks from attacks that may originate from the data network.
  • Follow Operating System hardening best practices for Cisco CallManagers and Voice Application servers.
  • Implement approved Anti-Virus software on Cisco CallManagers and voice application servers.
  • For additional information about IP telephony network security best practices refer to:
    IP Telephony SRND for Cisco CallManager 3.3

Workarounds for Systems Protected by Standalone CSA Agents

Cisco CSA for CallManager, CCC, Emergency Responder, IPCC Express, IP IVR, and IP Queue Manager

Cisco CSA for ICM, IPCC Enterprise, and IPCC Hosted Version 4.5.1 build 616

  • Disabling or uninstalling the CSA agent is a workaround this particular issue but leaves the workstation or server at risk to all other issues that the agent provides protection against. Disabling or uninstalling the CSA agent should only be considered as a last resort.
  • Uninstall procedures can be found in the following document:
    CiscoICM70-CSA-Installation-User-Guide.pdf which is available at:
    http://www.cisco.com/pcgi-bin/tablebuild.pl/csa10-crypto
  • There are no additional workarounds for this vulnerability. Please see the Obtaining Fixed Software section for appropriate solutions to resolve this vulnerability.

Cisco CSA for CVP 3.0 and 3.1 version 4.5.0 build 573. This version is used by CVP 3.0 and 3.1 and CVP VXML Server

  • Disabling or uninstalling the CSA agent is a workaround this particular issue but leaves the workstation or server at risk to all other issues that the agent provides protection against. Disabling or uninstalling the CSA agent should only be considered as a last resort.
  • Uninstall procedures can be found in the following document:
    CiscoCVP-CSA-InstallationGuide.pdf which is available at:
    http://www.cisco.com/pcgi-bin/tablebuild.pl/csa-cvp-20
  • There are no additional workarounds for this vulnerability. Please refer to the Obtaining Fixed Software section for appropriate solutions to resolve this vulnerability.

Obtaining Fixed Software

Cisco has made free software available to address this vulnerability for affected customers. 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 can 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.

Do not contact either "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 agreement 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 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@cisco.com

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.

Exploitation and Public Announcements

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

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-20051129-csa

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 1.0

2005-November-29

Initial 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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