Web Cache Entanglement: Novel Pathways to Poisoning

Summary: PortSwigger researcher James Kettle published research showing that caches parse, transform, and normalize the Host header and request line, creating gaps that allow cache poisoning attacks. He demonstrated the technique against real targets, including persistently poisoning every page on an online newspaper, compromising the administration interface on an internal DoD intelligence website, and disabling Firefox updates globally.
What's compelling: Kettle found the cache-key hole on Cloudflare and Fastly; Fastly patched it, but Cloudflare declined, and a single request can persistently take down a route to Cloudflare's login page.

Read the original at PortSwigger Research ↗

Topics: Vulnerabilities & Patching
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