Discovery / credits: Malvuln - (c) 2021  
Original source:  
Vulnerability: Port Bounce Scan (MITM)  
Description: The malware listens on TCP port 8181 (default) and has an FTP component that listens on port 1212 and accepts null creds. 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: d57536189430fd75e45f53845e9b3f94  
Vuln ID: MVID-2021-0267  
Dropped files: opeC248.exe  
Disclosure: 07/03/2021  
nmap -n -Pn -b "":""@ -p22,23,80 -v  
Starting Nmap 7.80 ( ) at 2021-06-27 22:06 Pacific Daylight Time  
Resolved FTP bounce attack proxy to (  
Attempting connection to ftp://:@  
Connected:220 ShangXing Ftp Server  
Login credentials accepted by FTP server!  
Initiating Bounce Scan at 22:06  
Discovered open port 80/tcp on  
Completed Bounce Scan at 22:06, 2.24s elapsed (3 total ports)  
Nmap scan report for  
Host is up.  
22/tcp closed ssh  
23/tcp closed telnet  
80/tcp open http  
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