VRT Advisories


VRT Rules 2009-04-10

Sourcefire VRT Rules Update

Date: 2009-04-10

Synopsis:

The Sourcefire VRT is aware of a vulnerability in Microsoft Powerpoint. This release also contains a fix for a known issue that affects Conficker detection.

Details:

Microsoft Powerpoint Code Execution (CVE-2009-0556):
Microsoft Powerpoint contains a programming error that may allow a remote attacker to execute code on a vulnerable system. An attacker would need to supply a specially crafted file to cause the fault and execute code.

A rule to detect attacks targeting this vulnerability is included in this release and is identified with GID 3 SID 15454.

Microsoft Security Advisory MS08-068:
A vulnerability in the Microsoft Server Message Block (SMB) protocol may allow a remote attacker to execute code on an affected system. The problem lies in the way that the protocol handles NTLM credentials when users attempt to login to a system.

An additional rule to detect attacks targeting this vulnerability is included in this release and is identified with GID 3, SID 15453.

Conficker Worm Update: SIDs 15449 and 15450 detect DNS traffic generated by Conficker-infected hosts, while SIDs 15451 and 15452 detect other Conficker-related traffic. The rules that detect variants C and D are more prone to the generation of false positive events than the A and B variant rules.

IMPORTANT: SIDs 15449 and 15450 may have an adverse affect on sensor performance. If this is the case, disable these two rules in favor of SIDs 15451 and 15452 which also detect Conficker traffic but are prone to false positive event generation.

Rule Pack Summary:

For a complete list of new and modified rules, click here.

Warning:

Sourcefire VRT rule packs often utilize enhancements made to Snort. Operators should upgrade to the latest revision or patch level for Snort to ensure these enhancements are available before using these rules.

About the VRT:

The Sourcefire VRT is a group of leading edge intrusion detection and prevention experts working to proactively discover, assess and respond to the latest trends in hacking activity, intrusion attempts and vulnerabilities. This team is also supported by the vast resources of the open source Snort community, making it the largest group dedicated to advances in the network security industry.