Cisco Secure Access Control Server (ACS) 3.x for Windows stores ACS administrator passwords and the master key in the registry with insecure permissions, which allows local users and remote administrators to decrypt the passwords by using Microsoft's cryptographic API functions to obtain the plaintext version of the master key.

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.

Buffer overflow in the administration service (CSAdmin) for Cisco Secure ACS before 3.1.2 allows remote attackers to cause a denial of service and possibly execute arbitrary code via a long user parameter to port 2002.