Cisco PIX and ASA appliances with 7.0 through 8.0 software, and Cisco Firewall Services Module (FWSM) 3.1(5) and earlier, allow remote attackers to cause a denial of service (device reload) via a crafted MGCP packet, aka CSCsi90468 (appliance) and CSCsi00694 (FWSM).

Internet Key Exchange (IKE) version 1 protocol, as implemented on Cisco IOS, VPN 3000 Concentrators, and PIX firewalls, allows remote attackers to cause a denial of service (resource exhaustion) via a flood of IKE Phase-1 packets that exceed the session expiration rate. NOTE: it has been argued that this is due to a design weakness of the IKE version 1 protocol, in which case other vendors and implementations would also be affected.

Cisco PIX/ASA 7.1.x before 7.1(2) and 7.0.x before 7.0(5), PIX 6.3.x before 6.3.5(112), and FWSM 2.3.x before 2.3(4) and 3.x before 3.1(7), when used with Websense/N2H2, allows remote attackers to bypass HTTP access restrictions by splitting the GET method of an HTTP request into multiple packets, which prevents the request from being sent to Websense for inspection, aka bugs CSCsc67612, CSCsc68472, and CSCsd81734.

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.