This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.
This signature detects attempts to exploit a vulnerability in Microsoft Agent which could result in remote code execution.
A remote code execution vulnerability exists in Microsoft Agent in the way that it processes URLs.
Microsoft Agent is an ActiveX control object which hosts a set of programmable software services that supports the presentation of interactive animated characters within the Windows interface. An exploitable condition exists in the Agent.Charactor.Load methods. When a malformed URL is processed, a memory corruption error may result that can cause an access violation or allow code execution.
Upgrade to the latest version of Microsoft Agent and ensure that all patches are applied.