{"id":"CVE-2026-75592","aliases":["GHSA-6j4c-mgqr-qv76"],"url":"https://o3.security/vulnerability/CVE-2026-75592","summary":"Kirby: Access to image files outside of the site root via path traversal in the media handling","details":"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.","published":"2026-08-31T20:49:41.341Z","modified":"2026-09-03T03:31:05.472302234Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Packagist","name":"getkirby/cms","fixedVersion":"4.9.5"},{"ecosystem":"Packagist","name":"getkirby/cms","fixedVersion":"5.5.2"}],"fix":{"url":"https://github.com/getkirby/kirby/commit/2b6fab950bc89d505ea89576bf71c8de614cc3b2","label":"getkirby/kirby@2b6fab9"},"references":[{"type":"WEB","url":"https://github.com/getkirby/kirby/releases/tag/4.9.5"},{"type":"WEB","url":"https://github.com/getkirby/kirby/releases/tag/5.5.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75592.json"},{"type":"ADVISORY","url":"https://github.com/getkirby/kirby/security/advisories/GHSA-6j4c-mgqr-qv76"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75592"},{"type":"FIX","url":"https://github.com/getkirby/kirby/commit/2b6fab950bc89d505ea89576bf71c8de614cc3b2"},{"type":"FIX","url":"https://github.com/getkirby/kirby/commit/e0dca5f709adc21b36f5549df2c0619bc59da56c"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-03T03:31:05.472302234Z"}}