FileZilla Security Best Practices

Keep your file transfers secure and protected

Security should be your top priority when transferring files. This comprehensive guide covers essential security practices for FileZilla, from choosing the right protocol to protecting your credentials and preventing unauthorized access.

⚠️ Critical Security Warning

Never use plain FTP for sensitive data! Plain FTP (port 21) sends your username, password, and all data in clear text, making it easy for attackers to intercept.

Always use SFTP or FTPS for secure, encrypted connections.

1. Use Secure Connection Protocols

✓ Recommended: SFTP

SFTP (SSH File Transfer Protocol) is the most secure option. It encrypts everything using SSH (Secure Shell).

How to use SFTP in FileZilla:

Open Site Manager (File → Site Manager)
Protocol: Select "SFTP - SSH File Transfer Protocol"
Port: Use 22 (standard SSH port)
Enter your server, username, and password
Connect

Benefits: Full encryption, works through most firewalls, widely supported

✓ Alternative: FTPS (FTP over TLS/SSL)

FTPS adds encryption to regular FTP using TLS/SSL (like HTTPS does for websites).

How to use FTPS:

Site Manager → New Site
Protocol: "FTP - File Transfer Protocol"
Encryption: "Require explicit FTP over TLS"
Port: Usually 21
Enter credentials and connect

Note: May require additional firewall configuration

✗ Avoid: Plain FTP

Do NOT use plain FTP unless absolutely necessary. It provides:

No encryption of any kind
Passwords visible in plain text on the network
All files transferred unencrypted
Vulnerable to man-in-the-middle attacks

2. Protect Your Passwords

Use Strong Passwords

Create passwords that are:

At least 12 characters long
Mix of uppercase, lowercase, numbers, and symbols
Unique (not reused from other accounts)
Random (use a password generator)

Enable Master Password (Optional)

If you save passwords in FileZilla, enable Master Password to encrypt them:

Edit → Settings → Passwords
Check "Use master password"
Enter a strong master password
You'll be prompted for this password when starting FileZilla

Don't Save Sensitive Passwords

For highly sensitive servers, choose "Ask for password" in Site Manager. You'll need to enter the password each time, but it won't be stored anywhere.

Use SSH Keys (Advanced)

For SFTP, you can use SSH key authentication instead of passwords:

Generate SSH key pair on your computer
Add public key to server
In Site Manager, set Logon Type: "Key file"
Browse to your private key file

More secure than passwords and convenient once set up.

3. Verify Server Identity

Certificate Warnings

When connecting via SFTP or FTPS, FileZilla may show certificate warnings:

• First connection: Verify the fingerprint with your hosting provider
• "Always trust" checkbox: Only check if you verified the certificate
• Changed certificate warning: Could indicate man-in-the-middle attack - investigate!

How to Verify Server Fingerprint

Contact your hosting provider and ask for the server's SSH fingerprint
Compare it with the fingerprint shown in FileZilla's certificate dialog
If they match, check "Always trust this certificate" and proceed
If they don't match, DO NOT CONNECT - it could be an attack

4. Secure Your Network Connection

⚠️ Avoid Public WiFi

Public WiFi networks (coffee shops, airports, hotels) are dangerous for FTP:

Even SFTP/FTPS can be vulnerable to sophisticated attacks
Other users on the network may be monitoring traffic
Fake hotspots can intercept connections

Solution: Use a VPN when on public networks, or avoid FTP altogether until you're on a trusted network.

✓ Use VPN for Extra Security

A Virtual Private Network (VPN) adds an extra encryption layer and hides your IP address. Recommended when traveling or on untrusted networks.

✓ Enable Firewall

Always have a firewall enabled on your computer. FileZilla works fine with firewalls when using SFTP or passive FTP mode.

5. Configure FileZilla Securely

✓ Clear Reconnect Data

FileZilla remembers recent connections. Clear this if others use your computer:

Edit → Clear private data → Check all boxes → OK

✓ Keep FileZilla Updated

Security vulnerabilities are patched in updates:

Help → Check for updates (do this monthly)

✓ Limit Connection Attempts

Prevent brute-force attacks on your server by limiting retries:

Edit → Settings → Connection → Maximum number of retries: 3

✓ Set Transfer Timeout

Disconnect idle connections automatically for security: Edit → Settings → Connection → Timeout: 300 seconds (5 minutes)

6. Server-Side Security Practices

Work with your hosting provider or sysadmin to implement these server security measures:

✓ Disable FTP, Use SFTP Only

Ask your host to disable plain FTP if possible

✓ IP Whitelisting

Only allow connections from specific IP addresses

✓ Fail2Ban Protection

Auto-block IPs after failed login attempts

✓ Regular Security Audits

Monitor logs for suspicious activity

✓ Disable Root FTP Access

Never allow root/admin FTP login

✓ Use Chroot Jails

Restrict users to their home directories

✓ FileZilla Security Checklist

🚨 If You Suspect a Security Breach

1.Change passwords immediately - Both FTP and server admin passwords
2.Check for unauthorized files - Look for malware, backdoors, or modified files
3.Review server logs - Check for suspicious login attempts or IP addresses
4.Contact hosting provider - They can help investigate and secure the server
5.Scan your computer - Use antivirus to check for malware that may have stolen credentials

📚 Learn More

Frequently Asked Questions

Is SFTP more secure than FTP?

Yes, SFTP (SSH File Transfer Protocol) encrypts all data including passwords, while plain FTP sends everything in clear text. Always use SFTP when possible for maximum security.

Should I save passwords in FileZilla?

It's convenient but not recommended for sensitive accounts. Use FileZilla's Master Password feature if you must save passwords, or enter them manually each time for critical servers.

What is the difference between FTPS and SFTP?

FTPS is FTP with TLS/SSL encryption (like HTTPS for web). SFTP uses SSH protocol. Both are secure, but SFTP is generally preferred as it's simpler and works better with firewalls.

Can someone intercept my FTP password?

Yes, if using plain FTP (port 21), passwords can be intercepted on the network. This is why SFTP or FTPS should always be used for sensitive data.