The EAP-FAST authentication module in Cisco Secure Access Control Server (ACS) 4.x before 4.2.1.15.11, when a RADIUS server configuration is enabled, does not properly parse user identities, which allows remote attackers to execute arbitrary commands via crafted EAP-FAST packets, aka Bug ID CSCui57636.

Stack-based buffer overflow in the CSAdmin service in Cisco Secure Access Control Server (ACS) for Windows before 4.1 and ACS Solution Engine before 4.1 allows remote attackers to execute arbitrary code via a crafted HTTP GET request.

Multiple unspecified vulnerabilities in the CSRadius service in Cisco Secure Access Control Server (ACS) for Windows before 4.1 and ACS Solution Engine before 4.1 allow remote attackers to cause a denial of service (crash) via a crafted RADIUS Access-Request packet. NOTE: it has been reported that at least one issue is a heap-based buffer overflow involving the Tunnel-Password attribute.

Stack-based buffer overflow in the CSRadius service in Cisco Secure Access Control Server (ACS) for Windows before 4.1 and ACS Solution Engine before 4.1 allows remote attackers to execute arbitrary code via a crafted RADIUS Accounting-Request packet.

The Downloadable RADIUS ACLs feature in Cisco PIX and VPN 3000 concentrators, when creating an ACL on the Cisco Secure Access Control Server (CS ACS), generates a random internal name for an ACL that is also used as a hidden user name and password, which allows remote attackers to gain privileges by sniffing the username from the cleartext portion of a RADIUS session, then using the password to log in to another device that uses CS ACS.

Multiple TCP implementations with Protection Against Wrapped Sequence Numbers (PAWS) with the timestamps option enabled allow remote attackers to cause a denial of service (connection loss) via a spoofed packet with a large timer value, which causes the host to discard later packets because they appear to be too old.

The CSAdmin web administration interface for Cisco Secure Access Control Server (ACS) 3.2(2) build 15 allows remote attackers to cause a denial of service (hang) via a flood of TCP connections to port 2002.

Cisco Secure Access Control Server (ACS) 3.2, when configured as a Light Extensible Authentication Protocol (LEAP) RADIUS proxy, allows remote attackers to cause a denial of service (device crash) via certain LEAP authentication requests.

Cisco Secure Access Control Server (ACS) 3.2(3) and earlier, when configured with an anonymous bind in Novell Directory Services (NDS) and authenticating NDS users with NDS, allows remote attackers to gain unauthorized access to AAA clients via a blank password.

Cisco Secure Access Control Server (ACS) 3.2(3) and earlier spawns a separate unauthenticated TCP connection on a random port when a user authenticates to the ACS GUI, which allows remote attackers to bypass authentication by connecting to that port from the same IP address.