CVE-2026-42575 PUBLISHED

apko doesn't verify downloaded apk packages against APKINDEX checksum (package substitution possible)

Assigner: GitHub_M
Reserved: 28.04.2026 Published: 09.05.2026 Updated: 09.05.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS Score: 7.5

Product Status

Vendor chainguard-dev
Product apko
Versions
  • Version < 1.2.7 is affected

References

Problem Types

  • CWE-345: Insufficient Verification of Data Authenticity CWE
  • CWE-494: Download of Code Without Integrity Check CWE