Checks for an identd (auth) server which is spoofing its replies.
Tests whether an identd (auth) server responds with an answer before we even send the query. This sort of identd spoofing can be a sign of malware infection, though it can also be used for legitimate privacy reasons.
nmap -sV --script=auth-spoof <target>
PORT STATE SERVICE REASON 113/tcp open auth syn-ack |_auth-spoof: Spoofed reply: 0, 0 : USERID : UNIX : OGJdvM
Author: Diman Todorov
License: Same as Nmap--See https://nmap.org/book/man-legal.html