GitHub Advisoryadvisory · Go

GHSA-hcwr-pq9g-rq3m apko doesn't verify downloaded apk packages against APKINDEX checksum (package substitution possible)

HIGH Published 2026-05-04 Modified 2026-05-13 Official page ↗
Aliases
CVE-2026-42575
Ecosystem
Go
Packages
chainguard.dev/apko
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weaknesses
CWE-345, CWE-494
Reviewed
2026-05-04

Affected packages

• Go chainguard.dev/apko: < 1.2.7 → fixed in 1.2.7

Description

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. Fix: No fix available yet. Acknowledgements apko thanks Oleh Konko from 1seal for discovering and reporting this issue.

Related

Alias · CVE (1)

  • CVE-2026-42575 apko allows users to build and publish OCI container images built from apk packages. vulnerability

Weakness · CWE (2)

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

References