{"id":"CVE-2026-119285","sourceIdentifier":"security-advisories@github.com","published":"2026-10-29T22:17:01.367","lastModified":"2026-10-30T19:37:07.073","vulnStatus":"Awaiting Analysis","cveTags":[],"descriptions":[{"lang":"en","value":"Fiber is an Express inspired web framework written in Go. From 2.52.1 until 2.52.3, the CORS middleware's validateDomain wildcard matcher in middleware/cors/utils.go strips the scheme and checks only a host suffix without requiring a dot boundary. An application configured with a wildcard-subdomain AllowOrigins value and AllowCredentials enabled can reflect an unrelated attacker-controlled origin whose host merely ends with the configured base domain. A user who visits that origin can expose authenticated cross-origin responses to the attacker's page; empty-label origins and later comma-space parsing hardening are outside this advisory. This issue is fixed in version 2.52.3."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"gofiber","product":"fiber","versions":[{"version":">= 2.52.1, < 2.52.3","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:L/A:N","baseScore":5.9,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":1.6,"impactScore":4.2}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Primary","description":[{"lang":"en","value":"CWE-346"},{"lang":"en","value":"CWE-942"}]}],"references":[{"url":"https://github.com/gofiber/fiber/commit/1aac6f618b6bd3e159d2449acb4232a2170b976b","source":"security-advisories@github.com"},{"url":"https://github.com/gofiber/fiber/pull/2915","source":"security-advisories@github.com"},{"url":"https://github.com/gofiber/fiber/releases/tag/v2.52.3","source":"security-advisories@github.com"},{"url":"https://github.com/gofiber/fiber/security/advisories/GHSA-g5jq-qmqr-qrwf","source":"security-advisories@github.com"}]}