VRT Advisories

VRT Rules 2006-10-02

Sourcefire VRT Update

Date: 2006-10-02


The Sourcefire VRT has continued research into vulnerabilities affecting Microsoft products. This rule pack reflects that effort by introducing new rules and improving the detection capabilities of previously released ones.


Microsoft Security Bulletin MS06-042 Microsoft Internet Explorer is vulnerable to a Denial of Service (DoS) which may possibly also lead to the execution of code of an attackers choosing. The error lies in the way that Internet Explorer tries to instantiate certain COM objects as ActiveX controls.

A rule to detect attacks targeting this vulnerability is included in this rule pack and is identified as sid 8425.

Microsoft Internet Explorer also suffers from a number of other vulnerabilities relating to the way it handles ActiveX controls. These vulnerabilities may also lead to a DoS condition and the possible execution of code of the attackers choosing.

Rules to detect attacks against these vulnerabilities are included in this rule pack and are identified as sids 8417 through 8424.

Rule Pack Summary:

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


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.