The default permissions for the RAS Administration key in Windows NT 4.0 allows local users to execute arbitrary commands by changing the value to point to a malicious DLL, aka one of the "Registry Permissions" vulnerabilities.
The default permissions for the MTS Package Administration registry key in Windows NT 4.0 allows local users to install or modify arbitrary Microsoft Transaction Server (MTS) packages and gain privileges, aka one of the "Registry Permissions" vulnerabilities.
Buffer overflow in RegAPI.DLL used by Windows NT 4.0 Terminal Server allows remote attackers to execute arbitrary commands via a long username, aka the "Terminal Server Login Buffer Overflow" vulnerability.
The NetBIOS Name Server (NBNS) protocol does not perform authentication, which allows remote attackers to cause a denial of service by sending a spoofed Name Conflict or Name Release datagram, aka the "NetBIOS Name Server Protocol Spoofing" vulnerability.