Microsoft Windows NT 4.0 Patch: NTLMSSP Privilege Update

This vulnerability exists because the NTLM Security Support Provider (NTLMSSP), which handles authentication requests associated with the NTLM Protocol, allows local user accounts to initiate a specially formed request to execute code by using LocalSystem security privileges. (These security privileges are equal to or greater than those of a local administrator account.) With these privileges, a malicious user with the ability to log on to a computer by using valid user credentials could exploit the vulnerability and send a request to the NTLMSSP that contains specially formatted commands to gain complete control over the computer.

For more information about this vulnerability, please read Microsoft Security Bulletin MS01-008.