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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| gofiber | fiber | >= 3.0.0-beta.2, < 3.3.0, < 2.52.14 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | golang-github-gofiber-fiber +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | govulncheck-vulndb | 0.0.20260727T201416-160000.1.1 | SUSE-SU-2026:23227-1, SUSE-SU-2026:23216-1 |
| SLES 16.0 | govulncheck-vulndb | 0.0.20260727T201416-160000.1.1 | SUSE-SU-2026:23227-1, SUSE-SU-2026:23216-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260727T201416-160000.1.1 | openSUSE-SU-2026:21551-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | gatus | 5.36.0-r8 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/gofiber/fiber/v2 | < 2.52.14 | 2.52.14 | GHSA-gcfq-8gqf-4876 |
| Go | github.com/gofiber/fiber/v3 | < 3.3.0 | 3.3.0 | GHSA-gcfq-8gqf-4876 |
Advisories 3
- SUSE-SU-2026:23227-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Aug 27, 2026
- SUSE-SU-2026:23216-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Aug 27, 2026
- openSUSE-SU-2026:21551-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Aug 12, 2026
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