{"id":"CVE-2026-112778","title":"Traefik before 2.11.46, 3.6.17, and 3.7.1 Cross-Namespace Resource Reference via Kubernetes Annotations","summary":"Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespa…","severity":"medium","cvss":6.4,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:H","cvssSource":"cna","cwe":["CWE-862"],"vendor":"traefik","product":"traefik","affected":["traefik < 2.11.46","traefik >= 3.0.0 < 3.6.17","traefik >= 3.7.0 < 3.7.1"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-19T21:15:57.381151Z"},"published":"2026-10-19","updated":"2026-10-19","sourceUpdated":"2026-10-19T21:16:12.196Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-112778","references":[{"url":"https://github.com/traefik/traefik/security/advisories/GHSA-rh7m-2m44-x32f","label":"GitHub Security Advisory (GHSA-rh7m-2m44-x32f)"},{"url":"https://www.vulncheck.com/advisories/traefik-before-2.11.46-3.6.17-and-3.7.1-cross-namespace-resource-reference-via-kubernetes-annotations","label":"VulnCheck Advisory: Traefik before 2.11.46, 3.6.17, and 3.7.1 Cross-Namespace Resource Reference via Kubernetes Annotations"}],"tags":["cve.org"],"ingestedAt":"2026-10-19T19:38:06.462Z","slug":"CVE-2026-112778","body":"## Overview\n\nTraefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.\n\n## Affected\n\n- `traefik < 2.11.46`\n- `traefik >= 3.0.0 < 3.6.17`\n- `traefik >= 3.7.0 < 3.7.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":35,"depthScoreParts":{"impact":35.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}