HTTP Reverse Proxy Vulnerability in Traefik Affects Multi-Tenant Clusters

CVE-2026-32695

What is CVE-2026-32695?

Traefik, an HTTP reverse proxy and load balancer, exposes vulnerabilities in its Knative provider configuration. Prior to versions 3.6.11 and 3.7.0-ea.2, it interpolates user-controlled values into critical rule expressions without adequate escaping. This flaw can allow attackers to bypass host restrictions in multi-tenant environments, potentially directing unauthorized traffic to sensitive services. Specifically, the misuse of Knative rules[].hosts[] enables exploitation by injecting arbitrary hosts, while unsafe rule construction via headers[].exact paves the way for additional rule-syntax injections. The vulnerabilities highlight significant security risks particularly in scenarios involving multi-tenant clusters.

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