{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45045","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-05-08T18:07:27.341Z","datePublished":"2026-07-08T19:26:26.580Z","dateUpdated":"2026-07-09T13:20:08.367Z"},"containers":{"cna":{"title":"Fiber: X-Real-IP Spoofing via Header.Add() in BalancerForward","problemTypes":[{"descriptions":[{"cweId":"CWE-290","lang":"en","description":"CWE-290: Authentication Bypass by Spoofing","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/gofiber/fiber/security/advisories/GHSA-gcfq-8gqf-4876","tags":["x_refsource_CONFIRM"],"url":"https://github.com/gofiber/fiber/security/advisories/GHSA-gcfq-8gqf-4876"},{"name":"https://github.com/gofiber/fiber/pull/4260","tags":["x_refsource_MISC"],"url":"https://github.com/gofiber/fiber/pull/4260"},{"name":"https://github.com/gofiber/fiber/pull/4495","tags":["x_refsource_MISC"],"url":"https://github.com/gofiber/fiber/pull/4495"},{"name":"https://github.com/gofiber/fiber/commit/1403cc8292da3220e9316960b4030cc722a0f396","tags":["x_refsource_MISC"],"url":"https://github.com/gofiber/fiber/commit/1403cc8292da3220e9316960b4030cc722a0f396"},{"name":"https://github.com/gofiber/fiber/commit/33c9501288ab47a429c8b5e701493f0c3c0af37d","tags":["x_refsource_MISC"],"url":"https://github.com/gofiber/fiber/commit/33c9501288ab47a429c8b5e701493f0c3c0af37d"},{"name":"https://github.com/gofiber/fiber/releases/tag/v2.52.14","tags":["x_refsource_MISC"],"url":"https://github.com/gofiber/fiber/releases/tag/v2.52.14"},{"name":"https://github.com/gofiber/fiber/releases/tag/v3.3.0","tags":["x_refsource_MISC"],"url":"https://github.com/gofiber/fiber/releases/tag/v3.3.0"}],"affected":[{"vendor":"gofiber","product":"fiber","versions":[{"version":">= 3.0.0-beta.2, < 3.3.0","status":"affected"},{"version":"< 2.52.14","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-07-08T19:26:26.580Z"},"descriptions":[{"lang":"en","value":"Fiber is an Express inspired web framework written in Go. Prior to 3.3.0 and 2.52.14, the BalancerForward proxy helper in middleware/proxy/proxy.go uses Header.Add() instead of Header.Set() when injecting X-Real-IP, allowing an attacker-supplied first X-Real-IP value to be forwarded to upstream servers for logging, rate limiting, and access control. This issue is fixed in version 3.3.0 and 2.52.14."}],"source":{"advisory":"GHSA-gcfq-8gqf-4876","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-09T13:19:42.395861Z","id":"CVE-2026-45045","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-09T13:20:08.367Z"}}]}}