CVE-2026-45045

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

08/07/2026

Last modified:

15/07/2026

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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 5.30 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): Low
Availability (A): None

Base Score 3.x

5.30

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:gofiber:fiber::::::go::*		2.52.14 (excluding)
cpe:2.3:a:gofiber:fiber::::::go::*	3.0.0 (including)	3.3.0 (excluding)

To consult the complete list of CPE names with products and versions, see this page

CVE-2026-45045

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools