How to join the desync endgame: Practical tips from pentester Tom Stacey

Summary: PortSwigger Research's paper 'HTTP/1.1 must die: the desync endgame' reports that James Kettle and a team of bug bounty hunters and researchers compromised 3 major CDNs using 2 new desync vulnerability classes, earning over $350,000 in payouts. Pentester Tom Stacey's guest post describes the research as a call to join the 'desync endgame,' with a new scanning technique for inconsistent HTTP header parsing already integrated into the latest version of HTTP Request Smuggler.
Why it matters: The paper's core claim is that HTTP/1.1 is inherently insecure because the boundaries between individual requests cannot be reliably identified, and nine years of patching parser discrepancies between intermediary components has failed to fix it. Three major CDNs were compromised with two new vulnerability classes, and the tooling to hunt for more is open source.

Read the original at PortSwigger Research ↗

Topics: Vulnerabilities & Patching
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