Improper access control in Traefik - #VU144549
Published: August 21, 2026
Vulnerability identifier: #VU144549
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to improper access control in the Kubernetes Ingress provider service middleware annotation handling when processing the traefik.ingress.kubernetes.io/service.middlewares Service annotation. A remote user can attach an operator-owned middleware from another provider to its own Service to disclose sensitive information.
Exploitation requires a namespace-limited tenant excluded from the allowlist and a security-sensitive middleware whose qualified name is known to the tenant.
Affected software
Traefik
Remediation
Install security update from vendor's website.
Traefik - update to 3.7.11