A security issue has been reported in various Cisco products, which can be exploited by malicious people to bypass certain security restrictions.

The security issue is caused due to an error in TACACS+ (Terminal Access Controller Access Control System Plus) and can be exploited to bypass the user authentication and gain unauthorized access to the devices.

Successful exploitation requires that TACACS+ authentication is incompletely configured (i.e. the AAA command specifies TACACS+ authentication, but the configuration lacks the "tacacs-server host" command).

The security issue affects the following products:
* Cisco Guard versions 5.0(1) and 5.0(3)
* Cisco Traffic Anomaly Detector versions 5.0(1) and 5.0(3)
* Anomaly Guard Module for the Cisco Catalyst 6500 switches/Cisco 7600 routers
* Traffic Anomaly Detector Module for the Cisco Catalyst 6500 switches/Cisco 7600 routers

NOTE: Versions prior to 5.0 and versions later than 5.0(3) are unaffected.

Solution
Update to version 5.1(4) or later.
Further details available in Customer Area

Provided and/or discovered by
The vendor credits Gerrit Wenig.

Changelog
Further details available in Customer Area

Original Advisory
http://www.cisco.com/warp/public/707/cisco-sa-20060215-guard.shtml

Deep Links
Links available in Customer Area