vsftpd

This guide is devised for system administrators and security experts who aim to secure their vsftpd (Very Secure FTP Daemon) servers. It includes a variety of hardening strategies, focusing on enhancing the security of FTP services.

Enforce FTPS (vsftpd.conf)​

FTPS (FTP over SSL/TLS) provides encryption for data transfers, protecting against eavesdropping and data interception. Enabling this ensures that all data transmitted is encrypted.

# /etc/vsftpd.conf  
ssl_enable=YES  

Disable Anonymous Login (vsftpd.conf)​

Disabling anonymous login reduces the risk of unauthorized access, ensuring that only authenticated users can access the FTP server.

# /etc/vsftpd.conf  
anonymous_enable=NO  

Employ Strong Encryption (vsftpd.conf)​

Using strong encryption for FTPS sessions enhances security. Specify high-grade ciphers to be used for encryption.

# /etc/vsftpd.conf  
ssl_ciphers=HIGH  

Limit User Access (vsftpd.conf)​

Restricting users to their home directories limits their access within the server, minimizing the risk of unauthorized file access or manipulation.

# /etc/vsftpd.conf  
chroot_local_user=YES  

Enable Logging (vsftpd.conf)​

Maintaining detailed logs aids in monitoring and investigating suspicious activities. Ensure that logging is enabled for tracking connections and transfers.

# /etc/vsftpd.conf  
xferlog_enable=YES  

Implement Rate Limiting (vsftpd.conf)​

Rate limiting controls the number of connection attempts within a specified timeframe, helping to mitigate brute-force attacks.

# /etc/vsftpd.conf  
max_per_ip=5  

Configure Passive Port Range (vsftpd.conf)​

Specifying a passive port range restricts the ports used for passive connections, reducing the attack surface exposed to potential intruders.

# /etc/vsftpd.conf  
pasv_min_port=40000  
pasv_max_port=40100  

Use Firewall to Restrict Access​

Employ a firewall to limit access to the FTP server, allowing connections only from trusted IP addresses or networks.

Regularly Update vsftpd​

Keeping vsftpd and its dependencies up-to-date is essential for protecting against vulnerabilities and exploits.