Answer in brief
CVE-2026-45045 records a Medium severity (CVSS 5.3) vulnerability in Fiber: X-Real-IP Spoofing via Header.Add() in BalancerForward. The current sources do not mark it as known exploited. The current feed maps gofiber/fiber (generic), github.com/gofiber/fiber/v2 (go), github.com/gofiber/fiber/v3 (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-45045 records a Medium severity (CVSS 5.3) vulnerability in Fiber: X-Real-IP Spoofing via Header.Add() in BalancerForward. The current sources do not mark it as known exploited. The current feed maps gofiber/fiber (generic), github.com/gofiber/fiber/v2 (go), github.com/gofiber/fiber/v3 (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps gofiber/fiber (generic), github.com/gofiber/fiber/v2 (go), github.com/gofiber/fiber/v3 (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| gofiber/fibergeneric | >= 3.0.0-beta.2, < 3.3.0 || < 2.52.14 | Not reported |
| github.com/gofiber/fiber/v2go | <=2.52.13 | 2.52.14 |
| github.com/gofiber/fiber/v3go | <=3.2.0 | 3.3.0 |
Published upstream
Jul 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 2, 2026
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.
Quoted source text, attributed separately from HOL analysis.
CVSS is 5.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps gofiber/fiber (generic), github.com/gofiber/fiber/v2 (go), github.com/gofiber/fiber/v3 (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| gofiber/fibergeneric | >= 3.0.0-beta.2, < 3.3.0 || < 2.52.14 | Not reported |
| github.com/gofiber/fiber/v2go | <=2.52.13 | 2.52.14 |
| github.com/gofiber/fiber/v3go | <=3.2.0 | 3.3.0 |
Published upstream
Jul 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 2, 2026
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.
Quoted source text, attributed separately from HOL analysis.