Description (CNA)
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 3.6.11 and 3.7.0-ea.2, Traefik's Knative provider builds router rules by interpolating user-controlled values into backtick-delimited rule expressions without escaping. In live cluster validation, Knative `rules[].hosts[]` was exploitable for host restriction bypass (for example `tenant.example.com`) || Host(`attacker.com`), producing a router that serves attacker-controlled hosts. Knative `headers[].exact` also allows rule-syntax injection and proves unsafe rule construction. In multi-tenant clusters, this can route unauthorized traffic to victim services and lead to cross-tenant traffic exposure. Versions 3.6.11 and 3.7.0-ea.2 patch the issue.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| traefik / traefik | affected < 3.6.11; affected >= 3.7.0-ea.1, < 3.7.0-ea.2 |
CWE
CWE-74
References
- https://github.com/traefik/traefik/security/advisories/GHSA-67jx-r9pv-98rj
- https://github.com/traefik/traefik/releases/tag/v3.6.11
- https://github.com/traefik/traefik/releases/tag/v3.7.0-ea.2
ADP enrichment
No English description supplied.
No references supplied.
A flaw was found in Traefik, an HTTP reverse proxy and load balancer. When using the Knative provider, Traefik incorrectly interpolates user-controlled values into router rule expressions without proper escaping. This vulnerability allows an attacker to inject malicious rule syntax, leading to a host restriction bypass. In multi-tenant environments, this can result in unauthorized traffic being routed to victim services, potentially exposing cross-tenant traffic.