On CentOS/RHEL:

Stop the service and completely remove the binary files compiled from the infected archive.

ssl_enable=YES allow_anon_ssl=NO force_local_data_ssl=YES force_local_logins_ssl=YES Use code with caution.

Download the latest source from the official site:

: Use chroot_local_user=YES to lock users into their home directories, preventing them from exploring the system files.

The most reliable automated detection tool is Nmap’s built‑in script:

The vsftpd (Very Secure FTP Daemon) software is known for its speed and stability. However, a specific historical version contains one of the most famous backdoors in cybersecurity history.

Set up alerting for any connections to port 6200:

Upgrading the software resolves the specific 2.3.4 backdoor, but standard FTP remains an inherently insecure protocol because it transmits credentials in plain text. Implement these additional hardening steps:

If the output returns vsftpd: version 2.3.4 , your installation may be compromised.