RSH service utility RSHSVC in Windows NT 3.5 through 4.0 does not properly restrict access as specified in the .Rhosts file when a user comes from an authorized host, which could allow unauthorized users to access the service by logging in from an authorized host.
Windows NT searches a user's home directory (%systemroot% by default) before other directories to find critical programs such as NDDEAGNT.EXE, EXPLORER.EXE, USERINIT.EXE or TASKMGR.EXE, which could allow local users to bypass access restrictions or gain privileges by placing a Trojan horse program into the root directory, which is writable by default.