Quick answers
- Is CVE-2026-65601 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-65601 being exploited in the wild.
- How severe is CVE-2026-65601?
- Medium severity, with a CVSS score of 4, published 22 July 2026.
- Which products and versions are affected?
- github.com/traefik/traefik (Go) SEMVER:introduced=0; Traefik (Go) SEMVER:introduced=3.7.0,fixed=3.7.7; Traefik Labs Traefik Proxy 3.7.0 to 3.7.6.
- Is there a fix for CVE-2026-65601?
- Yes. Traefik (Go): upgrade to 3.7.7 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-65601 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-65601?
- Check whether you run github.com/traefik/traefik (Go), Traefik (Go) or Traefik Labs Traefik Proxy 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
- Traefik (Go): upgrade to 3.7.7 or later
go get Traefik@v3.7.7
Technical details
A namespace-confusion vulnerability exists in Traefik's Kubernetes Gateway API provider when resolving 'HTTPRoute.spec.rules[].backendRefs[].filters[].extensionRef'. The root cause is that Traefik incorrectly reuses the backend Service's namespace instead of the HTTPRoute's namespace when resolving extension filters. A low-privileged attacker with 'ReferenceGrant' access to a cross-namespace Service can bind a Traefik 'Middleware' from that backend namespace without explicit authorization. If the bound middleware is configured to inject identity headers (e.g., X-WEBAUTH-USER), the attacker can achieve unauthorized authenticated state in downstream applications. This issue is fixed in version 3.7.7.
Affected products
- Traefik Labs Traefik >= 3.7.0, < 3.7.7
Identifiers
- CVE-2026-65601
- GHSA-qq9q-x9w4-chhj
- GO-2026-6198
Timeline
- 2026-07-09: advisory: Initial GitHub Advisory published
- 2026-08-05: patched: Fix released in version 3.7.7