CVE-2026-71325

Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef

Published Aug 6, 2026 CVSS 4.0 · 4.8 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-62fc-8686-hfmq Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef
History
Type Values Removed Values Added
CPEs cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 4.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Traefik
Traefik traefik
Vendors & Products Traefik
Traefik traefik
Type Values Removed Values Added
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.
Title Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef
Weaknesses CWE-653
CWE-863
References
Metrics cvssV4_0

{'score': 4.8, '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 7, 2026, 5:09 PM
Reserved
Aug 5, 2026, 6:14 PM
Status
Analyzed
Published
Aug 6, 2026, 10:18 PM
Modified
Sep 16, 2026, 8:46 PM