{"affected":[{"defaultStatus":"unaffected","ecosystem":"golang","packageName":"github.com/go-chi/chi/v5","product":"chi","source":"CNA: VulnCheck","vendor":"go-chi","versions":[{"lessThan":"5.5.0","status":"affected","version":"0","versionType":"semver"},{"status":"unaffected","version":"5.5.0","versionType":"semver"}]}],"cveId":"CVE-2026-118681","cwes":["CWE-288"],"description":"go-chi chi before 5.5.0 contains an authentication bypass in middleware.SupressNotFound, which calls Match with the live routing context and leaves a mounted router's parameter and child suffix in place for dispatch against the outer router. Unauthenticated attackers can request a mounted path whose suffix matches an outer public route, skipping the mounted authentication middleware and retrieving tenant-scoped data when that outer handler trusts the retained mount parameter.","epss":{"date":"2026-11-02","percentile":0.1561,"score":0.00244},"exploits":[{"kind":"exploit","source":"ADP: CISA-ADP","url":"https://github.com/go-chi/chi/security/advisories/GHSA-rqrp-8cg2-5958"}],"kev":null,"metrics":[{"score":6.3,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","version":"4.0"},{"score":3.7,"severity":"low","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}],"modifiedAt":1793712164537,"publishedAt":1793213992523,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/go-chi/chi/security/advisories/GHSA-rqrp-8cg2-5958"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/go-chi-chi-before-5.5.0-authentication-bypass-via-supressnotfound-middleware"},{"source":"ADP: CISA-ADP","tags":["exploit"],"url":"https://github.com/go-chi/chi/security/advisories/GHSA-rqrp-8cg2-5958"}],"remediation":[],"revision":"5f81cdcf4d69271d7c9ecd7dad39c21f4de9d4cac40a558b2abc93ce94ceb4bc","sources":[{"modifiedAt":1793712164537,"name":"CNA: VulnCheck","retrievedAt":1793714958494,"url":"https://www.cve.org/CVERecord?id=CVE-2026-118681"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793714963368,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-118681"}],"ssvc":{"assessedAt":1793712118146,"automatable":"no","exploitation":"poc","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"go-chi chi before 5.5.0 Authentication Bypass via SupressNotFound Middleware","updatedAt":1793714963368}