CVE-2026-27017

A flaw was found in uTLS. When using GREASE Encrypted ClientHello ECH, uTLS versions 1.6.0 through 1.8.0 may exhibit a fingerprint mismatch with Chrome. This occurs due to an inconsistent selection of cipher suites between the outer ClientHello and the ECH, potentially allowing a remote observer ...

uTLS has a fingerprint vulnerability from GREASE ECH mismatch for Chrome parrots

There is a fingerprint mismatch with Chrome when using GREASE ECH, having to do with ciphersuite selection. When Chrome selects the preferred ciphersuite in the outer ClientHello and the ciphersuite for ECH, it does so consistently based on hardware support. That means, for example, if it prefers...