Cisco IOS AAA RADIUS Authentication Bypass Vulnerability

Bugtraq ID:	14092
Class:	Failure to Handle Exceptional Conditions
CVE:
Remote:	Yes
Local:	No
Published:	Jun 29 2005 12:00AM
Updated:	Jun 29 2005 12:00AM
Credit:	The vendor announced this vulnerability.
Vulnerable:	Cisco IOS 12.4 Cisco IOS 12.3YS Cisco IOS 12.3YR Cisco IOS 12.3YQ Cisco IOS 12.3YN Cisco IOS 12.3YL Cisco IOS 12.3YK Cisco IOS 12.3YJ Cisco IOS 12.3YI Cisco IOS 12.3YH Cisco IOS 12.3YG Cisco IOS 12.3YF Cisco IOS 12.3YD Cisco IOS 12.3YB Cisco IOS 12.3YA Cisco IOS 12.3XY Cisco IOS 12.3XX Cisco IOS 12.3XW Cisco IOS 12.3XU Cisco IOS 12.3XT Cisco IOS 12.3XS Cisco IOS 12.3XR Cisco IOS 12.3XQ Cisco IOS 12.3XN Cisco IOS 12.3XM Cisco IOS 12.3XL Cisco IOS 12.3XK Cisco IOS 12.3XJ Cisco IOS 12.3XI Cisco IOS 12.3XH Cisco IOS 12.3XG Cisco IOS 12.3XF Cisco IOS 12.3XE Cisco IOS 12.3XD Cisco IOS 12.3XC Cisco IOS 12.3XB Cisco IOS 12.3XA Cisco IOS 12.3T Cisco IOS 12.3JA Cisco IOS 12.3BW Cisco IOS 12.3BC Cisco IOS 12.3B Cisco IOS 12.3 Cisco IOS 12.2ZP Cisco IOS 12.2ZO Cisco IOS 12.2ZN Cisco IOS 12.2ZL Cisco IOS 12.2ZJ Cisco IOS 12.2ZH Cisco IOS 12.2ZG Cisco IOS 12.2ZF Cisco IOS 12.2ZE Cisco IOS 12.2ZD Cisco IOS 12.2ZC Cisco IOS 12.2ZB Cisco IOS 12.2YY Cisco IOS 12.2YW Cisco IOS 12.2YV Cisco IOS 12.2YU Cisco IOS 12.2YT Cisco IOS 12.2YR Cisco IOS 12.2YQ Cisco IOS 12.2YP Cisco IOS 12.2YN Cisco IOS 12.2YM Cisco IOS 12.2YL Cisco IOS 12.2YJ Cisco IOS 12.2YH Cisco IOS 12.2YG Cisco IOS 12.2YF Cisco IOS 12.2YD Cisco IOS 12.2YC Cisco IOS 12.2YB Cisco IOS 12.2YA Cisco IOS 12.2XW Cisco IOS 12.2XT Cisco IOS 12.2XQ Cisco IOS 12.2XM Cisco IOS 12.2XL Cisco IOS 12.2XK Cisco IOS 12.2XJ Cisco IOS 12.2XI Cisco IOS 12.2XH Cisco IOS 12.2XG Cisco IOS 12.2XF Cisco IOS 12.2XE Cisco IOS 12.2XD Cisco IOS 12.2XC Cisco IOS 12.2XB Cisco IOS 12.2T Cisco IOS 12.2SXE Cisco IOS 12.2SXD Cisco IOS 12.2SE Cisco IOS 12.2MX Cisco IOS 12.2MC Cisco IOS 12.2MB Cisco IOS 12.2JK Cisco IOS 12.2JA Cisco IOS 12.2EZ Cisco IOS 12.2EY Cisco IOS 12.2EWA Cisco IOS 12.2EW Cisco IOS 12.2CZ Cisco IOS 12.2CY Cisco IOS 12.2CX Cisco IOS 12.2BZ Cisco IOS 12.2BY Cisco IOS 12.2BX Cisco IOS 12.2BW Cisco IOS 12.2BC Cisco IOS 12.2B
Not Vulnerable:	Cisco IOS 12.4(1) Cisco IOS 12.3(8)YI Cisco IOS 12.3(8)YH Cisco IOS 12.3(8)YG Cisco IOS 12.3(8)YD Cisco IOS 12.3(8)XY5 Cisco IOS 12.3(8)T4 Cisco IOS 12.3(14)YQ Cisco IOS 12.3(14)T Cisco IOS 12.3(11)YS Cisco IOS 12.3(11)YR Cisco IOS 12.3(11)YN Cisco IOS 12.3(11)YL Cisco IOS 12.3(11)YK Cisco IOS 12.3(11)YJ Cisco IOS 12.3(11)YF Cisco IOS 12.3(11)XL Cisco IOS 12.3(11)T Cisco IOS 12.3(10) Cisco IOS 12.2SW Cisco IOS 12.2(25)SEB2 Cisco IOS 12.2(18)SXD5

Cisco IOS AAA RADIUS Authentication Bypass Vulnerability

Cisco IOS Remote Authentication Dial In User Service (RADIUS) is prone to a remote authentication bypass vulnerability.

The issue manifests when Cisco IOS is configured to employ AAA RADIUS authentication and is configured to use 'none' as a fallback method.

A remote attacker may exploit this issue to bypass authentication and gain unauthorized access to the affected service.

Cisco IOS AAA RADIUS Authentication Bypass Vulnerability

No exploit is required.

Cisco IOS AAA RADIUS Authentication Bypass Vulnerability

Solution:
The vendor has released an advisory (cisco-sa-20050629-aaa) and updates to address this issue. The advisory also contains workaround information, customers are advised to read the advisory thoroughly and apply all appropriate workarounds or updates that are recommended by the vendor.

Cisco IOS AAA RADIUS Authentication Bypass Vulnerability

References:

• Cisco Security Advisory: RADIUS Authentication Bypass (Cisco)