CVE-2026-25140: apko affected by potential unbounded resource consumption in expandapk.ExpandApk on attacker-controlled .apk streams

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-04 · updated 2026-06-17
Weakness: CWE-400

Description

apko allows users to build and publish OCI container images built from apk packages. From version 0.14.8 to before 1.1.1, an attacker who controls or compromises an APK repository used by apko could cause resource exhaustion on the build host. The ExpandApk function in pkg/apk/expandapk/expandapk.go expands .apk streams without enforcing decompression limits, allowing a malicious repository to serve a small, highly-compressed .apk that inflates into a large tar stream, consuming excessive disk space and CPU time, causing build failures or denial of service. This issue has been patched in version 1.1.1.

Affected products

chainguard-dev apko: from 0.14.8 before 1.1.1 — fixed in 1.1.1

How to fix

Upgrade to a fixed version: chainguard-dev apko 1.1.1. Check the vendor advisory for mitigations.

References

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