Hack the Cache

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Cache plays an important role in modern web application. It helps web apps to deliver data faster, offload backend traffic. However, it also raise certain security issues if not configured properly. Normally, cache sits inside Reverse Proxy Server. So, before going deep how to hack cache, we first need to know what Reverse Proxy Server is and how cache works.

What is Reverse Proxy Server?

In modern web app, there normally a Reverse Proxy Server sits between the front end and the application servers, its primary responsibility is to redirect traffic to appropriate application server. A simple diagram of how a Reverse Proxy Server works is like below:

So, most requests to a web app would direct to a Reverse Proxy Server first. Then, Reverse Proxy would depends on functions, traffics of each application server to redirect client’s request to different Application Server.

So, in general, Reverse Proxy Server normally has a few functions like below:

• Hide the Real IP of the Web Server — As client would only send request to Reverse Proxy Server, client only knows the IP of Reverse Proxy Server’s IP, but not the IP of real server behind…