ModSecurity is a powerful web application layer firewall for Apache web servers. It monitors the whole HTTP traffic to a site without affecting its functionality and when it detects an intrusion attempt, it blocks it. The firewall additionally keeps a more comprehensive log for the traffic than any web server does, so you'll manage to keep track of what's happening with your sites a lot better than if you rely simply on conventional logs. ModSecurity uses security rules based on which it helps prevent attacks. For example, it recognizes whether anyone is attempting to log in to the admin area of a specific script multiple times or if a request is sent to execute a file with a certain command. In these cases these attempts trigger the corresponding rules and the firewall program hinders the attempts immediately, after that records comprehensive details about them inside its logs. ModSecurity is amongst the best software firewalls out there and it can protect your web applications against thousands of threats and vulnerabilities, especially if you don’t update them or their plugins often.