Cisco Security Advisory – Multiple vulnerabilities exist in the Cisco Firewall Services Module (FWSM). These vulnerabilities occur in the processing of specific Hypertext Transfer Protocol (HTTP), Secure HTTP (HTTPS), Session Initiation Protocol (SIP), and Simple Network Management Protocol (SNMP) traffic. If verbose logging is enabled for debugging purposes, a vulnerability exists when the FWSM processes packets destined to itself. All of these vulnerabilities may result in a reload of the device. An additional vulnerability is included in this advisory in which the manipulation of access control lists (ACLs) that make use of object groups may corrupt the ACL and create a situation where unwanted traffic may be permitted or desirable traffic may be blocked.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/54437/cisco-sa-20070214-fwsm.txt
Source: https://packetstormsecurity.com/files/54437/Cisco-Security-Advisory-20070214-fwsm.html