Cisco Network Access Control (NAC) Guest Server RADIUS Authentication Bypass Vulnerability

Bugtraq ID:	47092
Class:	Access Validation Error
CVE:	CVE-2011-0963
Remote:	Yes
Local:	No
Published:	Mar 30 2011 12:00AM
Updated:	Mar 30 2011 12:00AM
Credit:	Reported by the vendor
Vulnerable:	Cisco NAC Guest Server 2.0.2 Cisco NAC Guest Server 2.0.1
Not Vulnerable:	Cisco NAC Guest Server 2.0.3

Cisco Network Access Control (NAC) Guest Server RADIUS Authentication Bypass Vulnerability

Cisco Network Access Control (NAC) Guest Server is prone to an authentication-bypass vulnerability.

Remote attackers can exploit this issue to gain unauthorized access to protected networks. Successfully exploiting this issue will lead to other attacks.

This issue is being monitored by Cisco Bug ID CSCtj66922.

Versions prior to Cisco Network Access Control (NAC) Guest Server 2.0.3 are vulnerable.

Cisco Network Access Control (NAC) Guest Server RADIUS Authentication Bypass Vulnerability

An attacker can use readily available network utilities to exploit this issue.

Cisco Network Access Control (NAC) Guest Server RADIUS Authentication Bypass Vulnerability

Solution:
The vendor has released updates and an advisory. Please see the referenced advisory for more information.

Cisco Network Access Control (NAC) Guest Server RADIUS Authentication Bypass Vulnerability

References:

• Cisco Homepage (Cisco )
  
• Cisco NAC Guest Server (Cisco)
  
• Cisco Security Advisory: Cisco Network Access Control Guest Server System Softwa (Cisco)