CVE-2026-32695 PUBLISHED

Traefik has Knative Ingress Rule Injection that Allows Host Restriction Bypass

Assigner: GitHub_M
Reserved: 13.03.2026 Published: 27.03.2026 Updated: 27.03.2026

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.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N
CVSS Score: 6.3

Product Status

Vendor traefik
Product traefik
Versions
  • Version < 3.6.11 is affected
  • Version >= 3.7.0-ea.1, < 3.7.0-ea.2 is affected

References

Problem Types

  • CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') CWE