CVE-2026-72815: GO-2026-5774 - Chi has an IP spoofing vulnerability in middleware.RealIP in github.com/go-chi/chi

CVE-2026-72815 · Severity: medium · CVSS 4 · Published 2026-08-14

go-chi chi versions >= 5.2.1 and before 5.3.0 contain an IP spoofing vulnerability in the RealIP middleware, which blindly trusts the first (leftmost) value of the X-Forwarded-For HTTP header. A remote attacker can bypass IP-based access control lists and rate-limiting mechanisms, and forge log entries, by supplying a spoofed IP address in the X-Forwarded-For header. The issue is fixed in version 5.3.0.

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

Quick answers

Is CVE-2026-72815 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-72815 being exploited in the wild.
How severe is CVE-2026-72815?
Medium severity, with a CVSS score of 4, published 14 August 2026.
Which products and versions are affected?
github.com/go-chi/chi/v5 (Go) SEMVER:introduced=5.2.1,fixed=5.3.0; github.com/go-chi/chi/v5/middleware (Go) SEMVER:introduced=5.2.1,fixed=5.3.0.
Is there a fix for CVE-2026-72815?
Yes. github.com/go-chi/chi/v5 (Go): upgrade to 5.3.0 or later; github.com/go-chi/chi/v5/middleware (Go): upgrade to 5.3.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-72815?
Check whether you run github.com/go-chi/chi/v5 (Go) or github.com/go-chi/chi/v5/middleware (Go) 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 5.3.0 or later
    go get github.com/go-chi/chi/v5@v5.3.0
  • github.com/go-chi/chi/v5/middleware (Go): upgrade to 5.3.0 or later
    go get github.com/go-chi/chi/v5/middleware@v5.3.0

Affected products

  • github.com/go-chi/chi/v5 (Go) SEMVER:introduced=5.2.1,fixed=5.3.0
  • github.com/go-chi/chi/v5/middleware (Go) SEMVER:introduced=5.2.1,fixed=5.3.0

Identifiers

  • CVE-2026-72815
  • GHSA-3fxj-6jh8-hvhx
  • GO-2026-5774

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