This tutorial will show you how to protect your web server from HTTPOXY. It contains sections for the most used Linux Distributions CentOS + RHEL, Debian, and Ubuntu. The HTTPOXY vulnerability which has been found recently is a vulnerability that affects applications that run in cgi or cgi-like environments. This means that the issue affects almost all web servers including Apache and Nginx and also most PHP applications. Even the mod_php mode on apache is affected.