Log in Start free

Vulnerability · Published Aug 6, 2026 · Assigned by GitHub_M

CVE-2026-71325Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef

Medium 4.8

In plain English

A medium-severity incorrect authorization in traefik from traefik. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)4.8Medium
Exploit odds (30 days)0.2%top 95.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/traefik/traefikno fix listedGHSA-62fc-8686-hfmq
Gogithub.com/traefik/traefikno fix listedGO-2026-6203
Gogithub.com/traefik/traefik/v22.11.54GHSA-62fc-8686-hfmq
Gogithub.com/traefik/traefik/v22.11.54GO-2026-6203
Gogithub.com/traefik/traefik/v33.7.10GHSA-62fc-8686-hfmq
Gogithub.com/traefik/traefik/v33.6.25, 3.7.10GO-2026-6203
Gogithub.com/traefik/traefik/v33.6.25GHSA-62fc-8686-hfmq

Affected products (as reported)

VendorProductVersions
traefik traefik < 2.11.54>= 3.0.0, < 3.6.25>= 3.7.0, < 3.7.10

Weakness: CWE-653, CWE-863 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

References