CVE-2026-42575: Chainguard-Dev Apko

High severity, CVSS 7.5. EPSS: 0.2% 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, apko verifies the signature on APKINDEX.tar.gz but never compares individually downloaded .apk packages against the checksum recorded in the signed index. The checksum is parsed and available via ChecksumString(), and the downloaded package control hash is computed, but the two values are never compared in getPackageImpl(). Mismatched packages are silently accepted. An attacker who can substitute download responses (compromised mirror, HTTP repository, poisoned CDN cache) can install arbitrary packages into built images. 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.