Abyss web server red code#

There may be multiple front-end and back-end servers, and front-end and back-end servers are often themselves chains of multiple servers. This model is often a simplification of reality.

Abyss web server red code#

This is where the application's server-side code runs. A 'back-end' server which the front-end server forwards requests to.These servers typically handle caching and load balancing, or act as web application firewalls (WAFs). A 'front-end' server which directly handles requests from users.BackgroundĪ chain of HTTP servers used by a web application can often be modelled as consisting of two components: This paper presents a new technique for identifying header smuggling and demonstrates how header smuggling can lead to cache poisoning, IP restriction bypasses, and request smuggling. Much of this exploration, especially recent request smuggling research, has developed new ways to hide HTTP request headers from some servers in the chain while keeping them visible to others – a technique known as 'header smuggling'. The attack surface created by this forwarding is increasingly receiving more attention, including the recent popularisation of cache poisoning and request smuggling vulnerabilities. Modern web applications typically rely on chains of multiple servers, which forward HTTP requests to one another.