Answer in brief
CVE-2026-72817 records a Medium severity (CVSS 6.5) vulnerability in go-chi chi 0.9.0 before 5.3.0 IP Spoofing via X-Forwarded-For. The current sources do not mark it as known exploited. The current feed maps go-chi/chi (generic), github.com/go-chi/chi/middleware (go), github.com/go-chi/chi/middleware (go), github.com/go-chi/chi/v2/middleware (go) and additional mapped packages. 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 6.5. 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 go-chi/chi (generic), github.com/go-chi/chi/middleware (go), github.com/go-chi/chi/middleware (go), github.com/go-chi/chi/v2/middleware (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| go-chi/chigeneric | >=0.9.0 <5.3.0 | 5.3.0 |
| github.com/go-chi/chi/middlewarego | >=0.9.0,<=1.5.5 | Not reported |
| github.com/go-chi/chi/middlewarego | >=0.9.0 | Not reported |
| github.com/go-chi/chi/v2/middlewarego | <=2.1.1 | Not reported |
| github.com/go-chi/chi/v2/middlewarego | >=0 | Not reported |
| github.com/go-chi/chi/v3/middlewarego | <=3.3.5 | Not reported |
| github.com/go-chi/chi/v3/middlewarego | >=0 | Not reported |
| github.com/go-chi/chi/v4/middlewarego | <=4.1.3 | Not reported |
| github.com/go-chi/chi/v4/middlewarego | >=0 | Not reported |
| github.com/go-chi/chi/v5go | >=0 <5.3.0 | 5.3.0 |
| github.com/go-chi/chi/v5/middlewarego | <5.3.0 | 5.3.0 |
| github.com/go-chi/chi/v5/middlewarego | >=0 <5.3.0 | 5.3.0 |
Published upstream
Aug 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
go-chi/chi versions 0.9.0 before 5.3.0 contains an IP spoofing vulnerability in the RealIP middleware, which resolves the request source IP (Request.RemoteAddr) using the first IP in the X-Forwarded-For header without validating trusted proxies. A malicious client can prepend a forged IP as the first value of the X-Forwarded-For header to spoof the request source IP, potentially bypassing access controls or falsifying request logs.
Quoted source text, attributed separately from HOL analysis.