apko `DiscoverKeys` has a panic on non-rsa jwks key that causes crash during key discovery

CVE-2026-42576 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

DiscoverKeys in pkg/apk/apk/implementation.go unconditionally type-asserts JWKS keys as *rsa.PublicKey without checking the key type. If a repository JWKS endpoint returns a non-RSA key (e.g. EC), the unchecked assertion panics and crashes apko. This affects any workflow that initializes the APK database and fetches repository keys. Affected versions <= 0.30.34.

Fix: No fix available yet.

Acknowledgements

apko thanks Oleh Konko from 1seal for discovering and reporting this issue.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2026-05-04 21:25:30 UTC
Updated
2026-05-13 13:42:40 UTC
GitHub reviewed
2026-05-04 21:25:30 UTC
NVD published
2026-05-09 20:16:29 UTC

EPSS Score

Score Percentile
0.03% 10.41%

CVSS Scores

Base score Version Severity Vector
6.5 3.1 —
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-m7hm-vm4x-28jf ↗
CVE CVE-2026-42576 ↗

CWEs

CWE id Name
CWE-704 Incorrect Type Conversion or Cast

Credits

  • 1seal (reporter)
  • antitree (analyst)
  • markusthoemmes (remediation_reviewer)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
go chainguard.dev/apko < 1.2.7 1.2.7 —

References

cvelogic Threat Intelligence