{"id":"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.","aliases":["GHSA-6j4c-mgqr-qv76"],"modified":"2026-09-03T03:31:05.472302234Z","published":"2026-08-31T20:49:41.341Z","database_specific":{"unresolved_ranges":[{"extracted_events":[{"fixed":"4.9.5"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"GitHub_M","cwe_ids":["CWE-22"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75592.json"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/getkirby/kirby","events":[{"introduced":"2ff182ba39ddea19fa1615bd3733f734b5e53842"},{"fixed":"2b6fab950bc89d505ea89576bf71c8de614cc3b2"},{"fixed":"e0dca5f709adc21b36f5549df2c0619bc59da56c"},{"fixed":"81689c7f1471beb1fa9fb9c686f6f071f8671c3c"}],"database_specific":{"extracted_events":[{"introduced":"5.0.0"},{"fixed":"5.5.2"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["5.5.1","5.5.0","5.4.4","5.4.3","5.4.2","5.4.1","5.4.0","5.3.3","5.3.2","5.3.1","5.3.0","5.2.3","5.2.2","5.2.1","5.2.0","5.1.4","5.1.3","5.1.2","5.1.1","5.1.0","5.0.4","5.0.3","5.0.2","5.0.1","5.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-75592.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N"}]}