CVE-2026-42051: Kirby CMS's system API endpoint leaks installed version and license data to authenticated users

medium Affects getkirby/cms. Feed 2026.10.29.1, updated 2026-10-28; published 2026-05-04; advisory modified 2026-05-13.

Kirby CMS's system API endpoint leaks installed version and license data to authenticated users

Package: getkirby/cms Composer
Affected versions: <4.9.0 or >=5.0.0 and <5.4.0
Fixed in: 4.9.0, 5.4.0
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (8.9th percentile)
Published: 2026-05-04
Source: osv.dev

References

CWE-862

NVD record getkirby/cms advisories

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