{"id":"CVE-2026-45045","revision":"4efe1eb3d70f458389c208bdaa5319e3","records":[{"revision":"4efe1eb3d70f458389c208bdaa5319e3","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-45045","aliases":[],"title":"Fiber: X-Real-IP Spoofing via Header.Add() in BalancerForward","description":"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.","state":0,"publishedAt":"2026-07-08T19:26:26.58+00:00","modifiedAt":"2026-07-09T13:20:08.367+00:00","affected":[{"ecosystem":"Vendor product","name":"fiber","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"gofiber\",\n                    \"product\": \"fiber\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 3.0.0-beta.2, < 3.3.0\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"< 2.52.14\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","score":5.3,"severity":"MEDIUM"}],"references":["https://github.com/gofiber/fiber/security/advisories/GHSA-gcfq-8gqf-4876","https://github.com/gofiber/fiber/pull/4260","https://github.com/gofiber/fiber/pull/4495","https://github.com/gofiber/fiber/commit/1403cc8292da3220e9316960b4030cc722a0f396","https://github.com/gofiber/fiber/commit/33c9501288ab47a429c8b5e701493f0c3c0af37d","https://github.com/gofiber/fiber/releases/tag/v2.52.14","https://github.com/gofiber/fiber/releases/tag/v3.3.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-45045","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-45045","identifiers":["CVE-2026-45045"]},"retained":false,"historicalAffected":[]}],"coverage":[]}