Lab: Exploiting HTTP request smuggling to perform web cache poisoning
Summary: This PortSwigger lab sets up a front-end and back-end server pair where the front-end does not support chunked encoding and is configured to cache certain responses. The goal is a request smuggling attack that poisons the cache so a later request for a JavaScript file is redirected to the exploit server, with the poisoned response alerting document.cookie.
What's compelling: A poisoned cache entry turns one smuggled request into a payload served to every user who requests that JavaScript file, and the lab notes the POST/GET sequence may need repeating several times before it takes - meaning the attack can succeed quietly on a retry rather than the first try.
Read the original at PortSwigger Research ↗
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- Vulnerabilities & Patching
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