Kyverno before 1.16.2 contains a server-side request forgery (SSRF) vulnerability in the APICall feature. The URL field in a Policy's ServiceCall configuration is not validated, so a user with namespace-level Policy creation permissions can direct Kyverno to make HTTP requests to arbitrary internal resources (e.g., cloud metadata endpoints such as 169.254.169.254 or other tenants' resources). Because Kyverno executes these requests using its cluster-wide high-privilege ServiceAccount (a Confused Deputy problem), the responses—potentially including other tenants' secrets and cloud IAM credentials—are returned in the PolicyReport and can be read by the attacker, breaking multi-tenant isolation.

Kyverno versions before 1.16.2 contain a server-side request forgery (SSRF) vulnerability in its APICall feature. The URL field in a Policy's ServiceCall configuration lacks proper validation, allowing users with namespace-level Policy creation permissions to direct Kyverno to make HTTP requests to arbitrary internal resources. This includes cloud metadata endpoints such as 169.254.169.254 and other tenants' internal resources. Kyverno executes these requests using its cluster-wide high-privilege ServiceAccount, creating a Confused Deputy problem. The responses, which may contain sensitive data such as other tenants' secrets and cloud IAM credentials, are returned in the PolicyReport and accessible to the attacker. This effectively breaks multi-tenant isolation in Kubernetes clusters using Kyverno. Users are advised to upgrade to Kyverno 1.16.2 or later to remediate this vulnerability.