NtWaitForSingleObject

NtWaitForSingleObject is used to wait until the specified object is in the signaled state or the time-out interval elapses. This function is commonly used by malware for evasion purposes.

Ntdll.dll

Evasion Injection

http://undocumented.ntinternals.net/index.html?page=UserMode%2FUndocumented%20Functions%2FNT%20Objects%2FType%20independed%2FNtWaitForSingleObject.html