Kirby is an open-source content management system. Prior to 4.9.5 and 5.5.2, depending on the release line, Kirby's media handler in src/Cms/Media.php allowed Kirby\Cms\Media::thumb() to append a path-bearing filename to a validated parent media directory. On nginx, PHP's built-in server, or Apache with AllowEncodedSlashes enabled, a remote attacker could submit encoded slash characters such as %2f in the filename and traverse outside the parent's media directory. Differences between responses for existing and nonexistent thumbnail configurations disclosed whether an arbitrary .json file existed, and a .json file containing a valid filename key could cause the referenced image to be returned and the job file to be deleted. The related file::version path in src/Filesystem/Asset.php also accepted ../ sequences outside the intended index root. This issue is fixed in versions 4.9.5 and 5.5.2.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-9vx2-j98c-p72w Kirby: Access to image files and limited access to JSON files outside of the site root via path traversal in the media handling
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 31 Aug 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Getkirby
Getkirby kirby
Vendors & Products Getkirby
Getkirby kirby

Mon, 31 Aug 2026 21:00:00 +0000

Type Values Removed Values Added
Description Kirby is an open-source content management system. Prior to 4.9.5 and 5.5.2, depending on the release line, Kirby's media handler in src/Cms/Media.php allowed Kirby\Cms\Media::thumb() to append a path-bearing filename to a validated parent media directory. On nginx, PHP's built-in server, or Apache with AllowEncodedSlashes enabled, a remote attacker could submit encoded slash characters such as %2f in the filename and traverse outside the parent's media directory. Differences between responses for existing and nonexistent thumbnail configurations disclosed whether an arbitrary .json file existed, and a .json file containing a valid filename key could cause the referenced image to be returned and the job file to be deleted. The related file::version path in src/Filesystem/Asset.php also accepted ../ sequences outside the intended index root. This issue is fixed in versions 4.9.5 and 5.5.2.
Title Kirby: Access to image files and limited access to JSON files outside of the site root via path traversal in the media handling
Weaknesses CWE-22
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-31T20:53:00.338Z

Reserved: 2026-08-17T23:49:03.449Z

Link: CVE-2026-75594

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-31T21:17:48.760

Modified: 2026-08-31T21:17:48.760

Link: CVE-2026-75594

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-31T22:30:06Z

Weaknesses