ModSecurity

ModSecurity is a plugin for Apache web servers that functions as a web app layer firewall. It's employed to stop attacks against script-driven websites by using security rules which contain certain expressions. That way, the firewall can block hacking and spamming attempts and preserve even Internet sites which are not updated often. For instance, multiple unsuccessful login attempts to a script admin area or attempts to execute a particular file with the objective to get access to the script shall trigger particular rules, so ModSecurity will block these activities the minute it identifies them. The firewall is extremely efficient because it screens the whole HTTP traffic to a site in real time without slowing it down, so it will be able to stop an attack before any harm is done. It furthermore maintains an exceptionally comprehensive log of all attack attempts that includes more information than conventional Apache logs, so you can later examine the data and take additional measures to improve the security of your sites if needed.