CVE-2026-79664: Lin-Snow ECH0

High severity, CVSS 7.4. EPSS: 0.3% chance of exploitation in the next 30 days.

Ech0 before 4.7.3 fails to properly revoke access tokens created with never-expire option, allowing attackers to maintain perpetual authenticated access after token theft. Three independent revocation mechanisms fail: logout panics on nil ExpiresAt field, RevokeToken skips when remainTTL is zero, and admin delete does not blacklist the JTI, leaving stolen tokens cryptographically valid until JWT secret rotation.

Affected products

• Lin-Snow ECH0: before 4.7.3 (fixed in 4.7.3)

Published 2026-08-25. Last modified 2026-09-23.