CVE-2023-42816

CVE-2023-42816 is a denial-of-service vulnerability affecting Kyverno, a Kubernetes policy engine, specifically within its Notary verifier component. An attacker with control over the registry from which Kyverno fetches signatures could return a malicious response, leading to Kyverno’s unavailability and blocking admission requests. This vulnerability is rated Medium (CVSS 5.3) due to its network attack vector and high impact on availability, though it requires high attack complexity and user interaction (in the sense of Kyverno making a request to a compromised registry). It primarily affects users building Kyverno from source (v1.11.0 main branch) and not official releases. There is no known active exploitation, public exploit code, or significant community discussion surrounding this CVE.