Auth bypass in Traefik
CVE-2026-54765
Traefik is an open source HTTP reverse proxy and load balancer. From v3.7.0 prior to v3.7.6, Traefik's Kubernetes Gateway API provider may resolve two accepted HTTPRoutes that target the same backend Service:port but configure different backendRef filters to the same child service and apply only one route's filter set to all requests reaching that backend. In Gateway deployments where backendRef filters set security-sensitive headers, such as tenant identity, authorization context, or values the backend trusts, an attacker who can create an accepted HTTPRoute sharing the same backend Service:port may cause their route's filter context to be applied to another route's requests, potentially crossing namespace boundaries when a ReferenceGrant permits cross-namespace targeting. This issue is fixed in version v3.7.6.
EPSS: 0.003 (20.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N.
Affected products
- Traefik — versions >= 3.7.0, < 3.7.6
Weakness classification (CWE)
References
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-54765?
- CVE-2026-54765 is a high-severity vulnerability in Traefik, classified under Improper Access Control. CVSS score: 8.5/10. Published 2026-07-06.
- How severe is CVE-2026-54765?
- High severity. CVSS v3 base score is 8.5 out of 10.