{"id":"UBUNTU-CVE-2026-45045","details":"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.","modified":"2026-10-17T12:58:22.104098469Z","published":"2026-07-08T20:16:00Z","upstream":["CVE-2026-45045"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-45045"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-45045"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/commit/1403cc8292da3220e9316960b4030cc722a0f396"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/commit/33c9501288ab47a429c8b5e701493f0c3c0af37d"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/pull/4260"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/pull/4495"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/releases/tag/v2.52.14"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/releases/tag/v3.3.0"},{"type":"REPORT","url":"https://github.com/gofiber/fiber/security/advisories/GHSA-gcfq-8gqf-4876"}],"affected":[{"package":{"name":"golang-github-gofiber-fiber","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/golang-github-gofiber-fiber?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.3.0-1","3.4.0-1","3.5.0-1","3.5.0-4"],"ecosystem_specific":{"binaries":[{"binary_version":"3.5.0-4","binary_name":"golang-github-gofiber-fiber-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45045.json"}},{"package":{"name":"golang-github-gofiber-fiber-v2","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/golang-github-gofiber-fiber-v2?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.52.13-2","2.52.13-3"],"ecosystem_specific":{"binaries":[{"binary_version":"2.52.13-3","binary_name":"golang-github-gofiber-fiber-v2-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45045.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}