Kyverno 1.18.0 before 1.19.2 contains a signature verification bypass in verifyImages because…

Why it is Yellow

• CVSS 9.1 critical

References

• https://github.com/kyverno/kyverno/security/advisories/GHSA-2r43-6962-xcw5
• https://www.vulncheck.com/advisories/kyverno-1.18.0-before-1.19.2-verifyimages-cache-signature-verification-bypass

Original description

Kyverno 1.18.0 before 1.19.2 contains a signature verification bypass in verifyImages because cached verification results are keyed by the image reference string (such as a tag) rather than bound to the verified digest, so cache hits skip signature and attestation checks. An attacker who can submit workloads and move a registry tag can warm the cache with a signed image, repoint the tag, and have Kyverno admit the workload and use mutateDigest to pin the unverified digest.