CVE-2026-42574
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk28th percentile - higher than 28% of all known CVEs
Summary
Vulnerability in apko (versions 0.14.8 through before 1.2.5) allows a crafted .apk to install a TypeSymlink tar entry pointing outside the build root. Subsequent entries in the archive can traverse that symlink to reach host paths the build user can write to.
Risk Assessment
An attacker can exploit this to write files outside the build root, potentially modifying critical system files or installing malware.
Recommendation
Upgrade apko to version 1.2.5 or later.
Other vulnerabilities in apko
See all- CVE-2026-42576Medium
In apko prior to version 1.2.7, the DiscoverKeys function 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.
- CVE-2026-42575High
apko, a tool for building OCI container images from apk packages, prior to version 1.2.7 verifies the signature on APKINDEX.tar.gz but never compares individually downloaded .apk packages against the checksum recorded in the signed index. An attacker who can substitute download responses (compromised mirror, HTTP repository, poisoned CDN cache) can install arbitrary packages into built images.
Original NVD description (English source)
apko allows users to build and publish OCI container images built from apk packages. From version 0.14.8 to before version 1.2.5, a crafted .apk could install a TypeSymlink tar entry whose target pointed outside the build root, and a subsequent directory-creation or file-write entry in the same or later archive could traverse that symlink to reach host paths the build user could write to. This issue has been patched in version 1.2.5.