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.
This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Fiber | Gofiber | * | 2.52.14 (excluding) |
| Fiber | Gofiber | 3.0.0 (including) | 3.3.0 (excluding) |