Is CVE-2026-114437 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-114437 being exploited in the wild.

How severe is CVE-2026-114437?

Medium severity, with a CVSS score of 4.8, published 21 October 2026.

Which products and versions are affected?

github.com/go-chi/chi/v5 (Go) <= 5.3.2, SEMVER:introduced=0,fixed=5.4.0; Go-Chi Chi before 5.4.0.

Is there a fix for CVE-2026-114437?

Yes. github.com/go-chi/chi/v5 (Go): upgrade to 5.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-114437 attacked?

It is attacked over the network.

Am I affected by CVE-2026-114437?

Check whether you run github.com/go-chi/chi/v5 (Go) or Go-Chi Chi at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-114437: Go Chi ClientIPFromXFF IP spoofing via X-Forwarded-For

Q: Is there a fix for CVE-2026-114437?

Yes. github.com/go-chi/chi/v5 (Go): upgrade to 5.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-114437 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-114437?

Check whether you run github.com/go-chi/chi/v5 (Go) or Go-Chi Chi at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-114437 · Severity: medium · CVSS 4.8 · Published 2026-10-21

The Chi web framework's ClientIPFromXFF middleware in Go, used to extract the real client IP from proxy headers, fails to verify that the direct TCP connection originates from a trusted proxy server. An attacker who can reach the server directly can forge an X-Forwarded-For header with a spoofed IP address to bypass IP-based access controls, converting a denied request into an allowed one.

Technologies: github.com/go-chi/chi/v5 (Go), Go-Chi Chi. Vendors: Go, Go-Chi.

Quick answers

Is CVE-2026-114437 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-114437 being exploited in the wild.
How severe is CVE-2026-114437?: Medium severity, with a CVSS score of 4.8, published 21 October 2026.
Which products and versions are affected?: github.com/go-chi/chi/v5 (Go) <= 5.3.2, SEMVER:introduced=0,fixed=5.4.0; Go-Chi Chi before 5.4.0.
Is there a fix for CVE-2026-114437?: Yes. github.com/go-chi/chi/v5 (Go): upgrade to 5.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-114437 attacked?: It is attacked over the network.
Am I affected by CVE-2026-114437?: Check whether you run github.com/go-chi/chi/v5 (Go) or Go-Chi Chi at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/go-chi/chi/v5 (Go): upgrade to 5.4.0 or later
```
go get github.com/go-chi/chi/v5@v5.4.0
```

Technical details

The ClientIPFromXFF middleware skips X-Forwarded-For entries in configured trusted CIDRs but does not validate that http.Request.RemoteAddr (the direct peer) belongs to a trusted CIDR before processing the header chain. An unauthenticated remote attacker can append a trusted-proxy IP and a spoofed client IP to X-Forwarded-For, causing middleware.GetClientIP to return an arbitrary address. The vulnerability requires the server to be directly reachable and relies on an application that gates access based on client IP.

Affected products

Go Chi Chi before 5.4.0

Identifiers

CVE-2026-114437
GHSA-j6qf-3m9c-vwj3

Timeline

2026-10-12: disclosed
2026-10-21: patched

References

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