CVE-2026-45045

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 v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/gofiber/fiber/commit/1403cc8292da3220e9316960b4030cc722a0f396	Patch
https://github.com/gofiber/fiber/commit/33c9501288ab47a429c8b5e701493f0c3c0af37d	Patch
https://github.com/gofiber/fiber/pull/4260	Issue Tracking Patch
https://github.com/gofiber/fiber/pull/4495	Issue Tracking Patch
https://github.com/gofiber/fiber/releases/tag/v2.52.14	Release Notes
https://github.com/gofiber/fiber/releases/tag/v3.3.0	Release Notes
https://github.com/gofiber/fiber/security/advisories/GHSA-gcfq-8gqf-4876	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:gofiber:fiber::::::go::*
	cpe:2.3:a:gofiber:fiber::::::go::*

History

No history.

Information

Published : 2026-07-08 20:16

Updated : 2026-07-15 20:50

NVD link : CVE-2026-45045

Mitre link : CVE-2026-45045

CVE.ORG link : CVE-2026-45045

JSON object : View

Products Affected

gofiber

fiber

CWE

CWE-290

Authentication Bypass by Spoofing

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