Microsoft has released a patch that eliminates a security vulnerability in Microsoft� Windows NT 4.0. The vulnerability could allow a locally logged on user to grant herself administrator level privileges.

A flaw in the NTLM Security Support Provider (NTLMSSP) service could potentially allow a non-administrative user to gain administrative control over the system. In order to perform this attack the user would need a valid login account and the ability to execute arbitrary code on the system. This vulnerability could only be exploited by an attacker who could log onto the affected machine interactively. However, best practices strongly suggest that unprivileged users not be allowed to interactively log onto business-critical servers like domain controllers, ERP servers, print and file servers, database servers, and others. If this recommendation has been followed, machines such as these would not be at risk from this vulnerability and, as a result, the machines most likely to be affected would be workstations and terminal servers.

Affected Software Versions

Patch Availability