{"items":[{"id":"NVI-00015255","kind":"vulnerability","title":"Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-62fc-8686-hfmq","CVE-2026-71325"],"plain_summary":"GitHub lists this reviewed advisory for github.com/traefik/traefik/v2, github.com/traefik/traefik/v3, github.com/traefik/traefik/v3, github.com/traefik/traefik. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-4af91512857914bd08ae356e11bf8684"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-4af91512857914bd08ae356e11bf8684","url":"https://github.com/advisories/GHSA-62fc-8686-hfmq","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-62fc-8686-hfmq","publisher":"GitHub Advisory Database","observed_at":"2026-11-03T02:28:46.523Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4af91512857914bd08ae356e11bf8684"],"technology":"github.com/traefik/traefik/v2","known_exclusions":[],"conditions_summary":"## Summary\n\nThere is a medium severity vulnerability in Traefik's Kubernetes CRD provider. When `providers.kubernetesCRD.allowCrossNamespace` is disabled — the default — cross-namespace `@kubernetescrd` references are rejected for middlewares, TLS options and HTTP/TCP ServersTransports, but the same restriction was not applied to `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. Traefik v2 releases and the unmaintained v3 minor lines below v3.6 are affected and will not receive a patch on their own line; the remedy for those users is upgrading to a maintained, patched release.\n\n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.11.54\n- https://github.com/traefik/traefik/releases/tag/v3.6.25\n- https://github.com/traefik/traefik/releases/tag/v3.7.10\n\n## For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/iss","public_affected_ranges":["<= 2.11.53"]},{"certainty":"source_listed","source_ids":["sr-4af91512857914bd08ae356e11bf8684"],"technology":"github.com/traefik/traefik/v3","known_exclusions":[],"conditions_summary":"## Summary\n\nThere is a medium severity vulnerability in Traefik's Kubernetes CRD provider. When `providers.kubernetesCRD.allowCrossNamespace` is disabled — the default — cross-namespace `@kubernetescrd` references are rejected for middlewares, TLS options and HTTP/TCP ServersTransports, but the same restriction was not applied to `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. Traefik v2 releases and the unmaintained v3 minor lines below v3.6 are affected and will not receive a patch on their own line; the remedy for those users is upgrading to a maintained, patched release.\n\n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.11.54\n- https://github.com/traefik/traefik/releases/tag/v3.6.25\n- https://github.com/traefik/traefik/releases/tag/v3.7.10\n\n## For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/iss","public_affected_ranges":[">= 3.0.0, <= 3.6.24"]},{"certainty":"source_listed","source_ids":["sr-4af91512857914bd08ae356e11bf8684"],"technology":"github.com/traefik/traefik/v3","known_exclusions":[],"conditions_summary":"## Summary\n\nThere is a medium severity vulnerability in Traefik's Kubernetes CRD provider. When `providers.kubernetesCRD.allowCrossNamespace` is disabled — the default — cross-namespace `@kubernetescrd` references are rejected for middlewares, TLS options and HTTP/TCP ServersTransports, but the same restriction was not applied to `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. Traefik v2 releases and the unmaintained v3 minor lines below v3.6 are affected and will not receive a patch on their own line; the remedy for those users is upgrading to a maintained, patched release.\n\n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.11.54\n- https://github.com/traefik/traefik/releases/tag/v3.6.25\n- https://github.com/traefik/traefik/releases/tag/v3.7.10\n\n## For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/iss","public_affected_ranges":[">= 3.7.0, <= 3.7.9"]},{"certainty":"source_listed","source_ids":["sr-4af91512857914bd08ae356e11bf8684"],"technology":"github.com/traefik/traefik","known_exclusions":[],"conditions_summary":"## Summary\n\nThere is a medium severity vulnerability in Traefik's Kubernetes CRD provider. When `providers.kubernetesCRD.allowCrossNamespace` is disabled — the default — cross-namespace `@kubernetescrd` references are rejected for middlewares, TLS options and HTTP/TCP ServersTransports, but the same restriction was not applied to `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. Traefik v2 releases and the unmaintained v3 minor lines below v3.6 are affected and will not receive a patch on their own line; the remedy for those users is upgrading to a maintained, patched release.\n\n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.11.54\n- https://github.com/traefik/traefik/releases/tag/v3.6.25\n- https://github.com/traefik/traefik/releases/tag/v3.7.10\n\n## For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/iss","public_affected_ranges":["<= 1.7.34"]}],"null_published_at":"2026-11-03T10:03:26.565Z","source_updated_at":"2026-08-06T16:38:37.000Z","source_disclosed_at":"2026-08-06T16:38:37.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-03T02:28:46.523Z"}],"next_cursor":null,"snapshot_revision":"42594"}