Fiber: X-Real-IP Spoofing via Header.Add() in BalancerForward (gofiber fiber)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.46 % · percentile 40 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
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.
Weaknesses (CWE)
- CWE-290 — Authentication Bypass by Spoofing
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
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N | GitHub_M |
| CVSS 3.1 | MEDIUM 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-gcfq-8gqf-4876 — GoFiber Vulnerable to X-Real-IP Spoofing via Header.Add() in BalancerForward
- GO-2026-5887 — GoFiber Vulnerable to X-Real-IP Spoofing via Header.Add() in BalancerForward in github.com/gofiber/fiber
European references
- ENISA EUVD · EUVD-2026-42351
- GCVE · GCVE-0-2026-45045
CERT-FR advisories
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*< 2.52.14cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*≥ 3.0.0 < 3.3.0
Affected products
| Product | Versions |
|---|---|
| gofiber · fiber | affected >= 3.0.0-beta.2, < 3.3.0 ; affected < 2.52.14 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |