Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/ba815d409cd714c0eac010b5970f6408.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Onalf
Vulnerability: Missing Authentication
Description: WinRemoteShell (Onalf) listens for commands on TCP port 2020. Interestingly, it will only start listening once it can connect outbound to SMTP port 25. Not much of a self respecting backdoor, as it allows anyone to logon without requiring a password. After logon you are greeted with Welcome to WinRemoteShell(c)Chernickevich http://onehalf.hotmail.ru.
Type: PE32
MD5: ba815d409cd714c0eac010b5970f6408
Vuln ID: MVID-2021-0042
Disclosure: 01/20/2021


Exploit/PoC:
TELNET x.x.x.x 2020


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