Linux security involves a set of measures and best practices to protect the system from attacks and unauthorized access. Here are some of the key points to keep in mind:
1. Regular updates
- Always keep your system and all installed packages up to date to close known security vulnerabilities. Use tools like apt , yum , or dnf , depending on your distribution.
2. Strong passwords
- Use complex passwords for all user accounts and consider using password managers. Also enforce password policies to avoid weak passwords.
3. User management
- Create only the user accounts you need and grant minimal permissions. Use sudo to temporarily gain administrator privileges instead of running directly as root.
4. Configure firewall
- Use a firewall like iptables or ufw to control access to your system and only allow necessary network traffic.
5. Security updates and patches
- Make sure security updates and patches are applied as soon as possible. Automatic updates are a good way to ensure this.
6. Intrusion Detection System (IDS)
- Implement an IDS such as AIDE (Advanced Intrusion Detection Environment) or OSSEC to detect irregular or suspicious activity.
7. Use SELinux or AppArmor
- Deploy security modules such as SELinux (Security-Enhanced Linux) or AppArmor to provide additional access controls to processes and files.
8. Secure SSH configuration
- Disable root login over SSH ( PermitRootLogin no ) and use key-based authentication instead of passwords. Change the default SSH port and use Fail2ban to prevent brute-force attacks.
9. Security monitoring and logging
- Enable and regularly check system logs ( /var/log ) and use tools such as logwatch or rsyslog to monitor suspicious activity.
10. Avoid unnecessary services
- Disable or remove unnecessary services and applications to reduce the attack surface.
11. Backup strategy
- Implement regular backups and ensure that they are stored securely to be able to restore data in case of emergency.
12. Access rights and file system
- Set strict permissions on files and directories. Avoid setting 777 permissions and use tools like chmod and chown to ensure correct permissions.
13. Secure network configuration
- Check and configure network interfaces securely. Use network security protocols like VPNs for secure connections.
By implementing these security measures, you can significantly reduce the likelihood of a security incident on your Linux system.
