Cisco Secure Access Control Server contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary commands. Updates are available.
A vulnerability in the EAP-FAST authentication module of Cisco Secure Access Control Server (ACS) versions 4.0 through 22.214.171.124 could allow an unauthenticated, remote attacker to execute arbitrary commands on the Cisco Secure ACS server. This vulnerability is only present when Cisco Secure ACS is configured as a RADIUS server.
The vulnerability is due to improper parsing of user identities used for EAP-FAST authentication. An attacker could exploit this vulnerability by sending crafted EAP-FAST packets to an affected device. An exploit could allow the attacker to execute arbitrary commands on the Cisco Secure ACS server and take full control of the affected server.
Cisco has confirmed the vulnerability in a security advisory and has released software updates.
Cisco Secure ACS for Windows versions 126.96.36.199 and prior are affected when configured as a RADIUS server with EAP-FAST authentication.
To exploit this vulnerability, it is likely that an attacker would need access to trusted, internal networks to send crafted EAP-FAST packets to an affected device. This access requirement decreases the likelihood of a successful exploit.
Cisco indicates through the CVSS score that functional exploit code exists and is publicly available.
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary commands on the underlying operating system that hosts the Cisco Secure ACS application in the context of the System user for Cisco Secure ACS running on Microsoft Windows. Successful exploitation could result in a complete system compromise.
The vulnerability is due to improper parsing of user identities that are used for EAP-FAST authentication by an affected device.
An unauthenticated, remote attacker could exploit this vulnerability by sending crafted EAP-FAST packets via UDP port 1812 or 1645 to an affected device. Successful exploitation could allow the attacker to execute arbitrary commands, which could result in a complete system compromise of an affected device.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems
Administrators are advised to monitor affected systems.
Cisco customers with active contracts can obtain updates through the Software Center at the following link: Cisco. Cisco customers without contracts can obtain upgrades by contacting the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via email at firstname.lastname@example.org.
The security vulnerability applies to the following combinations of products.
Cisco Secure Access Control Server (ACS) for Windows
4.0 Base | 4.0.1 Base | 188.8.131.52 Base | 4.1 Base | 184.108.40.206 Base | 220.127.116.11 Base | 18.104.22.168 Base | 22.214.171.124 Base | 126.96.36.199 Base | 188.8.131.52 Base
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