Discovery / credits: Malvuln - (c) 2021  
Original source:  
Threat: Backdoor.Win32.Zxman  
Vulnerability: Missing Authentication   
Description: Backdoor.Win32.Zxman by Zx-man listens on TCP port 2048 for commands. However, anyone who can reach the infected host can take control as there is no authentication in place. Not much of a self-respecting backdoor. Third party intruders or incident responders who logon will be greeted with a welcome screen and help menu allowing for a wide-range of commands.  
Welcome to REMOTE_CONTROL_SYSTEM by Zx-man (  
Commands List: etc..  
Type: PE32  
MD5: 6b2a9304d1c7a63365db0f9fd12d39b0  
Vuln ID: MVID-2021-0041  
Disclosure: 01/20/2021   
TELNET x.x.x.x 2048  
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