CVE-2026-42575
apko doesn't verify downloaded apk packages against APKINDEX checksum (package substitution possible)
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](https://1seal.org/) for discovering and reporting this issue.
How to fix CVE-2026-42575
To remediate CVE-2026-42575, upgrade the affected package to a fixed version below.
- —upgrade to 1.2.7 or later
Is CVE-2026-42575 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 1.2.7
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |