Cisco Pix Firewall any version

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.

By design, the "established" command on the Cisco PIX firewall allows connections from one host to arbitrary ports of a target host if an alternative conduit has already been allowed, which can cause administrators to configure less restrictive access controls than intended if they do not understand this functionality.

The encryption algorithms for enable and passwd commands on Cisco PIX Firewall can be executed quickly due to a limited number of rounds, which make it easier for an attacker to decrypt the passwords using brute force techniques.

Cisco Secure PIX Firewall does not properly identify forged TCP Reset (RST) packets, which allows remote attackers to force the firewall to close legitimate connections.