ModSecurity : ModSecurity is an open source web application firewall. Working embedded in the web server, or standalone as a network appliance, it detects and prevents attacks against web applications.
In order to use mod_security, you need to turn on EPEL repo under CentOS / RHEL Linux.
RHEL 5.x / CentOS 5.x Users
Type the following command as root user to install repo:
# rpm -Uvh http://download.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm
RHEL 6.x / CentOS 6.x Users
Type the following command as root user to install repo:
# rpm -Uvh http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm
Once repo is turned on, type the following command to install ModSecurity:
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