Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Gofiber | Fiber | < 2.52.14 |
Related Weaknesses (CWE)
References
- https://github.com/gofiber/fiber/commit/1403cc8292da3220e9316960b4030cc722a0f396Patch
- https://github.com/gofiber/fiber/commit/33c9501288ab47a429c8b5e701493f0c3c0af37dPatch
- https://github.com/gofiber/fiber/pull/4260Issue TrackingPatch
- https://github.com/gofiber/fiber/pull/4495Issue TrackingPatch
- https://github.com/gofiber/fiber/releases/tag/v2.52.14Release Notes
- https://github.com/gofiber/fiber/releases/tag/v3.3.0Release Notes
- https://github.com/gofiber/fiber/security/advisories/GHSA-gcfq-8gqf-4876ExploitVendor Advisory
FAQ
What is CVE-2026-45045?
CVE-2026-45045 is a vulnerability with a CVSS score of 5.3 (MEDIUM). 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 injec...
How severe is CVE-2026-45045?
CVE-2026-45045 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-45045?
Check the references section above for vendor advisories and patch information. Affected products include: Gofiber Fiber.