{"api_version":"1","generated_at":"2026-10-29T15:10:22+00:00","cve":"CVE-2026-118264","urls":{"html":"https://cve.report/CVE-2026-118264","api":"https://cve.report/api/cve/CVE-2026-118264.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-118264","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-118264"},"summary":{"title":"Echo: Rejected WebSocket upgrades can bypass Echo route-level access controls","description":"Echo is a Go web framework. From 4.0.0 until 4.16.1 and 5.4.1, Echo's Proxy middleware selects a raw tunnel from a client WebSocket upgrade request before verifying that the configured upstream accepted the upgrade. If the upstream rejects the upgrade with an ordinary keep-alive response, later HTTP requests on the connection are sent directly to that upstream without passing through Echo's router or route-specific middleware. 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