{"id":"CVE-2026-114437","state":"PUBLISHED","title":"Chi Client IP Spoofing in ClientIPFromXFF via X-Forwarded-For","description":"In the Golang Chi web framework, the ClientIPFromXFF middleware skips any X-Forwarded-For entry in a configured trusted CIDR but never verifies that the direct TCP peer in http.Request.RemoteAddr belongs to that CIDR. A client that can reach the Go server directly can therefore append a trusted-looking proxy address and choose the client IP returned by middleware.GetClientIP.\n\nThis issue affects chi before 5.4.0.","publishedAt":"2026-10-21T13:52:25.617Z","updatedAt":"2026-10-21T17:19:13.809Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","source":"tenable"},"assigner":"tenable","products":["go-chi chi"],"affected":[{"vendor":"go-chi","product":"chi","packageName":"github.com/go-chi/chi/v5","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"5.4.0","versionType":"semver"}],"collectionURL":"https://pkg.go.dev"}],"references":["https://www.tenable.com/security/research/tra-2026-66","https://github.com/go-chi/chi/security/advisories/GHSA-j6qf-3m9c-vwj3"],"weaknesses":["CWE-348"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/114xxx/CVE-2026-114437.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-114437","state":"PUBLISHED","datePublished":"2026-10-21T13:52:25.617Z","dateUpdated":"2026-10-21T17:19:13.809Z","assignerShortName":"tenable","assignerOrgId":"5ac1ecc2-367a-4d16-a0b2-35d495ddd0be","dateReserved":"2026-10-21T13:42:40.246Z"},"containers":{"cna":{"title":"Chi Client IP Spoofing in ClientIPFromXFF via X-Forwarded-For","descriptions":[{"lang":"en","value":"In the Golang Chi web framework, the ClientIPFromXFF middleware skips any X-Forwarded-For entry in a configured trusted CIDR but never verifies that the direct TCP peer in http.Request.RemoteAddr belongs to that CIDR. A client that can reach the Go server directly can therefore append a trusted-looking proxy address and choose the client IP returned by middleware.GetClientIP.\n\nThis issue affects chi before 5.4.0."}],"affected":[{"vendor":"go-chi","product":"chi","packageName":"github.com/go-chi/chi/v5","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"5.4.0","versionType":"semver"}],"collectionURL":"https://pkg.go.dev"}],"references":[{"url":"https://www.tenable.com/security/research/tra-2026-66"},{"url":"https://github.com/go-chi/chi/security/advisories/GHSA-j6qf-3m9c-vwj3"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE","baseSeverity":"MEDIUM","baseScore":4.8,"vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N"}},{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":6.3,"vectorString":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-348","lang":"en","description":"CWE-348 Use of Less Trusted Source","type":"CWE"}]}],"providerMetadata":{"shortName":"tenable","orgId":"5ac1ecc2-367a-4d16-a0b2-35d495ddd0be","dateUpdated":"2026-10-21T13:52:25.617Z"},"datePublic":"2026-10-21T15:00:00.000Z","credits":[{"lang":"en","value":"Joshua Martinelle","type":"finder"}],"source":{"discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 1.0.5"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-114437","role":"CISA Coordinator","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-21T15:16:38.882767Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-21T17:19:13.809Z"}}]}}}