Cisco Security Advisory: Cisco Secure Access Control Server for Windows Admin Buffer Overflow Vulnerability

Type securityvulns
Reporter Securityvulns
Modified 2003-04-23T00:00:00



Cisco Security Advisory: Cisco Secure Access Control Server for Windows Admin Buffer Overflow Vulnerability =======================================================================

Revision 1.0

For Public Release 2003 April 23 08:00 (GMT)


Cisco Secure ACS for Windows is vulnerable to a buffer overflow on the administration service which runs on TCP port 2002. Exploitation of this vulnerability results in a Denial of Service, and can potentially result in system administrator access. Cisco is providing repaired software, and customers are recommended to install patches or upgrade at their earliest opportunity. Workarounds can be implemented, and consist of blocking external access to port 2002 on the ACS.

This issue is documented in Cisco Bug ID CSCea51366. This issue is also being referenced in the Mitre CVE as CAN-2003-0210.

This advisory is available at

Affected Products

Cisco Secure ACS versions up to and including version 2.6.4 , 3.0.3, and 3.1.1 are affected by this vulnerability.

No other Cisco products are affected by this vulnerability. Specifically, Cisco Secure ACS for UNIX is NOT affected by this vulnerability.


Cisco Secure ACS for Windows provides a Web-based management interface, termed CSAdmin, which listens on TCP port 2002. A buffer overflow vulnerability occurs during CSAdmin process servicing login requests. Once a sufficiently long user parameter is received by the server, this can cause the buffer overflow, which would typically result in the service hanging until it can be restarted. It is possible that a buffer overflow could be performed that would result in the compromise of the system and permit remote control of the system.

This issue is resolved by applying the patch files to repair the CSAdmin program, and will be repaired in future versions of CSAdmin.

Bug ID CSCea51366


Customer installations of Cisco Secure ACS for Windows that provide unrestricted access to all ports on the server may be vulnerable to a Denial of Service, or potentially a root compromise. It is recommended that customers upgrade to repaired versions of Cisco Secure ACS, or install Cisco Secure ACS such that external access to management interfaces is eliminated or severely restricted.

Software Versions and Fixes

Fixes to the CSAdmin will be included in ACS for Windows versions 3.0.4, 3.1.2, and later, which will become available on the Cisco website. Patch files for 2.6.4, 3.0.3, and 3.1.1 are currently available on the Cisco website. Customers running versions earlier than 2.6.4, 3.0.3, or 3.1.1 will need to upgrade to those versions to apply the patch files.

The patch files that resolve this problem for specific versions are as follows:

* ACS 3.1(1) -
* ACS 3.0(3) -
* ACS 2.6 -

Customers that are logged into the Cisco website can download these files at:

Obtaining Fixed Software

Cisco is offering free software upgrades to remedy this vulnerability for all affected customers. Customers may only install and expect support for the feature sets they have purchased.

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

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 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 or patch files by contacting the Cisco Technical Assistance Center (TAC). In those cases, customers may only upgrade to a later version of the same release to which they are entitled, or the patch files for that release. 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)
* email: <>.

See for additional TAC contact information, including special localized telephone numbers and instructions and e-mail addresses for use in various languages.

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 "" or "" for software upgrades


It is recommended that customers patch systems, or upgrade to repaired versions of Cisco Secure ACS. Alternatively, the vulnerability can be mitigated by blocking access to the ACS on port 2002, as well as strictly limiting the access to internal hosts that have reason to connect to the ACS. This can be accomplished with access control lists on routers or firewalls.

Exploitation and Public Announcements

The Cisco PSIRT was made aware of this vulnerability by the NSFOCUS Security Team, who are also releasing an advisory regarding this issue. Their advisory will be available at

Cisco is unaware of malicious use of the vulnerabilities described in this advisory.

Status of This Notice: Final

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


This notice will be posted on Cisco's worldwide website at 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:

* &#40;includes CERT/CC&#41;
* Various internal Cisco mailing lists

Future updates of this notice, if any, will be placed on Cisco's worldwide web. Users concerned about this problem are encouraged to check the URL given above for any updates.

Revision History

Revision 1.0 2003-April-23 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 This includes instructions for press inquiries regarding Cisco security notices. All Cisco Security Advisories are available at

This notice is Copyright 2003 by Cisco Systems, Inc. This notice may be redistributed freely after the release date given at the top of the text, provided that redistributed copies are complete and unmodified, and include all date and version information.

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