Vulnerability · Published Feb 4, 2026 · Assigned by GitHub_M
CVE-2026-25122apko is vulnerable to unbounded resource consumption in expandapk.Split on attacker-controlled .apk streams
Medium 5.5
In plain English
A medium-severity uncontrolled resource consumption in apko from chainguard-dev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
apko allows users to build and publish OCI container images built from apk packages. From version 0.14.8 to before 1.1.0, expandapk.Split drains the first gzip stream of an APK archive via io.Copy(io.Discard, gzi) without explicit bounds. With an attacker-controlled input stream, this can force large gzip inflation work and lead to resource exhaustion (availability impact). The Split function reads the first tar header, then drains the remainder of the gzip stream by reading from the gzip reader directly without any maximum uncompressed byte limit or inflate-ratio cap. A caller that parses attacker-controlled APK streams may be forced to spend excessive CPU time inflating gzip data, leading to timeouts or process slowdown. This issue has been patched in version 1.1.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | chainguard.dev/apko | 1.1.0 | GHSA-6p9p-q6wh-9j89 |
| Go | chainguard.dev/apko | 1.1.0 | GO-2026-4406 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| chainguard-dev | apko | >= 0.14.8, < 1.1.0 |
Weakness: CWE-400 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H