CVE-2026-55677: Labstack Echo

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Echo is a Go web framework. Prior to 4.15.3 and 5.2.0, Echo's router and static file handler disagree on URL path decoding. The router matches routes using the raw encoded path (preserving %2F as-is), while StaticDirectoryHandler unescapes %2F to / before resolving filesystem paths. This allows an attacker to bypass route-level access controls and read static files without authorization. This vulnerability is fixed in 4.15.3 and 5.2.0.

Affected products

• Labstack Echo: before 4.15.3 (fixed in 4.15.3); from 5.0.0, before 5.2.0 (fixed in 5.2.0)

Published 2026-06-26. Last modified 2026-06-26.