FreeBSD : snort -- DCE/RPC preprocessor vulnerability (afdf500f-c1f6-11db-95c5-000c6ec775d9)
Critical Nessus Plugin ID 24686
SynopsisThe remote FreeBSD host is missing a security-related update.
DescriptionA IBM Internet Security Systems Protection Advisory reports :
Snort is vulnerable to a stack-based buffer overflow as a result of DCE/RPC reassembly. This vulnerability is in a dynamic-preprocessor enabled in the default configuration, and the configuration for this preprocessor allows for auto-recognition of SMB traffic to perform reassembly on. No checks are performed to see if the traffic is part of a valid TCP session, and multiple Write AndX requests can be chained in the same TCP segment. As a result, an attacker can exploit this overflow with a single TCP PDU sent across a network monitored by Snort or Sourcefire.
Snort users who cannot upgrade immediately are advised to disable the DCE/RPC preprocessor by removing the DCE/RPC preprocessor directives from snort.conf and restarting Snort. However, be advised that disabling the DCE/RPC preprocessor reduces detection capabilities for attacks in DCE/RPC traffic. After upgrading, customers should re-enable the DCE/RPC preprocessor.
SolutionUpdate the affected package.