CVE-2026-79659: Lin-Snow ECH0

High severity, CVSS 7.7. EPSS: 0.3% chance of exploitation in the next 30 days.

Ech0 before 4.7.3 contains a server-side request forgery vulnerability in the fetchPeerConnectInfo function that uses unvalidated HTTP requests instead of safe request methods with URL validation. Authenticated attackers can supply arbitrary URLs to access internal services and cloud metadata endpoints by triggering connection health checks or peer connection operations.

Affected products

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

Published 2026-08-25. Last modified 2026-10-08.