A AegiFlow
MEDIUMCVSS 6.9EPSS 0.5%

CVE-2026-75592

CVE-2026-75592 updated by NVD

Published
2026-09-02
Modified
2026-09-10
EPSS percentile
38%
Sources
github-advisory, nvd

Summary

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 used incomplete filesystem containment checks in src/Filesystem/Dir.php and src/Filesystem/F.php through Kirby\Filesystem\Dir::realpath() and Kirby\Filesystem\F::realpath(). The checks accepted a sibling directory whose path shared the intended root's string prefix, such as /var/www/site2 next to /var/www/site, because they did not require an exact match or a DIRECTORY_SEPARATOR boundary. A remote attacker could use Kirby\Cms\Media::thumb() to create and access thumbnails from image files in a PHP-readable sibling directory when that directory contained a valid .json thumbnail job file, potentially exposing staging sites, backups, or other internal sites and deleting the job file during processing. This issue is fixed in versions 4.9.5 and 5.5.2.

Affected packages

EcosystemPackageAffected versionsFixed versions
Packagistgetkirby/cms4.9.5, 5.5.2

Remediation: Upgrade to 4.9.5 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.