ModSecurity

ModSecurity is a plugin for Apache web servers which acts as a web application layer firewall. It's employed to stop attacks against script-driven Internet sites by employing security rules which contain particular expressions. This way, the firewall can prevent hacking and spamming attempts and shield even websites that aren't updated on a regular basis. For example, multiple failed login attempts to a script administrative area or attempts to execute a particular file with the intention to get access to the script will trigger certain rules, so ModSecurity will block these activities the second it identifies them. The firewall is quite efficient since it screens the whole HTTP traffic to an Internet site in real time without slowing it down, so it could stop an attack before any damage is done. It furthermore maintains an exceptionally comprehensive log of all attack attempts which contains more info than conventional Apache logs, so you can later examine the data and take additional measures to improve the security of your Internet sites if required.