CVE-2026-71325 Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef
Attackers can bypass namespace isolation in Traefik to access or reroute backend services from other namespaces when cross-namespace references are disabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-71325?
CVE-2026-71325 is a medium-severity missing authorization vulnerability in Traefik Traefik, published on 6 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Traefik is an open-source edge router that makes publishing services a fun and easy experience. Prior to 2.11.54, 3.6.25, and 3.7.10, cross-namespace @kubernetescrd references are not rejected for TraefikService backend references resolved by the service resolver. A tenant confined by RBAC to a single namespace can therefore bind its own router to a TraefikService owned by another namespace and expose or reroute that namespace's backend, defeating the namespace isolation allowCrossNamespace=false is meant to enforce. This issue is fixed in version 2.11.54, 3.6.25, 3.7.10.
Which versions are affected by CVE-2026-71325?
11 open source packages ship an affected version, including github.com/traefik/traefik/v3, github.com/traefik/traefik and github.com/traefik/traefik/v2. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/traefik/traefik/v3 Go | From 3.0.0 | 3.6.25, 3.7.10 |
github.com/traefik/traefik/v3 Go | From 3.0.0 | 3.6.25 |
github.com/traefik/traefik/v3 Go | From 3.0.0 | 3.6.25 |
github.com/traefik/traefik/v3 Go | From 3.7.0 | 3.7.10 |
github.com/traefik/traefik/v3 Go | From 3.7.0 | 3.7.10 |
github.com/traefik/traefik Go | All versions | None |
5 more packages
github.com/traefik/traefik Go | All versions to 1.7.34 | None |
github.com/traefik/traefik Go | All versions to 1.7.34 | None |
github.com/traefik/traefik/v2 Go | All versions | 2.11.54 |
github.com/traefik/traefik/v2 Go | All versions | 2.11.54 |
github.com/traefik/traefik/v2 Go | All versions | 2.11.54 |
Products include Traefik Traefik.
How do I fix CVE-2026-71325?
Upgrade github.com/traefik/traefik/v3 to a fixed version for your release line: 3.6.25 or 3.7.10.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-71325 being exploited?
There is no known exploitation of CVE-2026-71325 in the wild and no public exploit code.
Other vulnerabilities in Traefik Traefik
- CVE-2024-45410 HTTP client can remove the X-Forwarded headers in Traefik
- CVE-2026-88877 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect
- CVE-2026-85595 Traefik before v2.11.55 and v3.0.0 through v3.7.10 Authentication Bypass via digestAuth
- CVE-2026-88007 Traefik HTTP/3 Backend NTLM Connection Reuse
- CVE-2026-88009 Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging
Sources
Also known as GHSA-62fc-8686-hfmq, GO-2026-6203, MINI-4j52-wjg6-hqfg, MINI-8f4c-p94f-3q63, MINI-cg9v-c46j-g57q.