Vulnerability Description
Echo is a Go web framework. Prior to 4.16.0 and 5.4.0, Echo's MethodOverride middleware accepts a safe HTTP method as the override target for a POST request. When MethodOverride is registered before CSRF in the post-routing middleware chain, route selection retains the original state-changing POST handler but the override changes the method before CSRF evaluates it, causing both token validation and Sec-Fetch-Site checks to be skipped. A cross-site exploit requires an authenticated victim and an override value that a browser-submitted request can control, such as the form getter used by the advisory reproducer; the default X-HTTP-Method-Override header getter is not settable by a cross-site form. This issue is fixed in 4.16.0 and 5.4.0.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/labstack/echo/commit/b838391e2eade87ae7e5a09d7bb5087bec271ec1
- https://github.com/labstack/echo/commit/fc410094b2f3415cf2bf5204082137b205bfd5af
- https://github.com/labstack/echo/releases/tag/v4.16.0
- https://github.com/labstack/echo/releases/tag/v5.4.0
- https://github.com/labstack/echo/security/advisories/GHSA-r7w9-592q-9vg4
FAQ
What is CVE-2026-118266?
CVE-2026-118266 is a vulnerability with a CVSS score of 5.3 (MEDIUM). Echo is a Go web framework. Prior to 4.16.0 and 5.4.0, Echo's MethodOverride middleware accepts a safe HTTP method as the override target for a POST request. When MethodOverride is registered before C...
How severe is CVE-2026-118266?
CVE-2026-118266 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-118266?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.