A vulnerability and a security issue have been reported in Cisco Firewall Services Module, which can be exploited by malicious people to cause a DoS (Denial of Service) or bypass certain security restrictions.

1) An unspecified error exists when inspecting malformed SIP packets. This can be exploited to cause the device to reload by sending specially crafted SIP packets.

Successful exploitation requires that "SIP fixup" is enabled, which is the default setting.

2) A security issue when manipulating ACLs (Access Control Lists) that make use of object groups can corrupt ACLs, resulting in ACEs (Access Control Entries) being skipped or not evaluated in order, which can be exploited to bypass certain security restrictions.

Note: Only an administrative user can change ACLs. Additionally, this does not affected devices which are reloaded after ACLs have been manipulated.

Solution
Update to version 2.3(4.12) or 3.1(3.24)

Provided and/or discovered by
Reported by the vendor.

Original Advisory
http://www.cisco.com/warp/public/707/cisco-sa-20070214-fwsm.shtml

Deep Links
Links available in Customer Area