CVE-2026-42137: Kirby CMS's `pages.access/list` and `files.access/list` permissions are not consistently checked in the Panel and REST API

high Affects getkirby/cms. Feed 2026.10.29.4, updated 2026-10-29; published 2026-04-30; advisory modified 2026-05-05.

Kirby CMS's `pages.access/list` and `files.access/list` permissions are not consistently checked in the Panel and REST API

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: high
Exploitation: not on CISA KEV · EPSS 0% (23.1th percentile)
Published: 2026-04-30
Source: osv.dev

References

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