CVE-2026-42576: Chainguard-Dev Apko

Medium severity, CVSS 6.5. EPSS: 0.5% chance of exploitation in the next 30 days.

apko allows users to build and publish OCI container images built from apk packages. Prior to version 1.2.7, DiscoverKeys in pkg/apk/apk/implementation.go unconditionally type-asserts JWKS keys as *rsa.PublicKey without checking the key type. If a repository JWKS endpoint returns a non-RSA key (e.g. EC), the unchecked assertion panics and crashes apko. This affects any workflow that initializes the APK database and fetches repository keys. This issue has been patched in version 1.2.7.

Affected products

• Chainguard-Dev Apko: before 1.2.7 (fixed in 1.2.7)

Published 2026-05-09. Last modified 2026-07-24.