Traefik versions 3.7.0 through 3.7.6 contain a namespace confusion vulnerability in the Kubernetes Gateway API provider. When resolving HTTPRoute.spec.rules[].backendRefs[].filters[].extensionRef, Traefik used the backend Service namespace instead of the HTTPRoute namespace. A low-privileged route author holding a ReferenceGrant for a cross-namespace Service could therefore bind a Traefik Middleware from the backend namespace without a separate grant for that middleware, potentially injecting trusted reverse-proxy identity headers into downstream requests. The issue is fixed in version 3.7.7.

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact High

Subsequent System Integrity Impact High

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
traefik traefik unaffected
Version Status Constraints
3.7.0 affected < 3.7.7
3.7.7 unaffected —

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Project Subscriptions

Vendors Products
Traefik Subscribe
Traefik Subscribe
Advisories

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Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/traefik/traefik/commit/26c96a3935cafb473f4a5bae1886560d9aa4e4f0 cve-icon
https://github.com/traefik/traefik/security/advisories/GHSA-qq9q-x9w4-chhj cve-icon
https://www.vulncheck.com/advisories/traefik-before-namespace-confusion-via-httproute-extensionref cve-icon
History

Wed, 22 Jul 2026 11:45:00 +0000

Type Values Removed Values Added
Description Traefik versions 3.7.0 through 3.7.6 contain a namespace confusion vulnerability in the Kubernetes Gateway API provider. When resolving HTTPRoute.spec.rules[].backendRefs[].filters[].extensionRef, Traefik used the backend Service namespace instead of the HTTPRoute namespace. A low-privileged route author holding a ReferenceGrant for a cross-namespace Service could therefore bind a Traefik Middleware from the backend namespace without a separate grant for that middleware, potentially injecting trusted reverse-proxy identity headers into downstream requests. The issue is fixed in version 3.7.7.
Title Traefik before 3.7.7 Namespace Confusion via HTTPRoute ExtensionRef
First Time appeared Traefik
Traefik traefik
Weaknesses CWE-863
CPEs cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*
Vendors & Products Traefik
Traefik traefik
References
Metrics cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-07-22T11:21:47.468Z

Reserved: 2026-07-22T10:48:36.000Z

Link: CVE-2026-65601

cve-icon Vulnrichment

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cve-icon NVD

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cve-icon Redhat

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cve-icon OpenCVE Enrichment

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Weaknesses