Port 42/TCP is a port used by WINS (the Microsoft Windows Internet Naming Service) which is the target of an increasingly popular stream of exploits over the Internet. The vulnerability has been designated MS04-045 by Microsoft. An advisory as well as updates can be found at the following address:https://://www.m.microsoft.com/en-us/security-updates/securitybulletins/2004/ms04-05/2004. The names reported by KAV for the malware which is causing this increase in port 42 traffic are Backdoor.Win32.Hzdoor.a and Exploit.MS04-011.a.”]
Source: https://securelist.com/the-meaning-of-life-the-universe-and-everything/29932/