CRLF-Powered Desync Attacks: Beheading HTTP Streams
Summary: PortSwigger researchers documented turning HTTP header injection into CRLF-powered desync attacks, including response queue poisoning that let them capture session cookies and auth tokens for thousands of applications hosted on a CDN. Case studies included a telecoms provider where 500 connections over 20 minutes yielded internal access tokens and a $20,000 bounty, and a payment provider where the desync occurred inside its Kubernetes cluster and returned credit card numbers and PII from multiple corporations.
Bottom line: A single injected header can turn a CDN or payment provider into a shared pipe that hands one customer's session cookies, auth tokens, and card data to another - and in one case the researchers accidentally logged thousands of live users into their own account before anyone noticed.
Read the original at PortSwigger Research ↗
- Topics
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