CVE-2026-75592 Kirby: Access to image files outside of the site root via path traversal in the media handling
Remote attackers can access and delete image files in sibling directories via path traversal in Kirby CMS media handling, exposing internal site data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-75592?
CVE-2026-75592 is a medium-severity path traversal vulnerability in getkirby kirby, published on 31 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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 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.
Weakness: CWE-22
Which versions are affected by CVE-2026-75592?
4 open source packages ship an affected version, including getkirby/cms.
| Package | Affected | Fixed in |
|---|---|---|
getkirby/cms Packagist | All versions | 4.9.5 |
getkirby/cms Packagist | All versions | 4.9.5 |
getkirby/cms Packagist | From 5.0.0 | 5.5.2 |
getkirby/cms Packagist | From 5.0.0 | 5.5.2 |
How do I fix CVE-2026-75592?
Upgrade getkirby/cms to a fixed version for your release line: 4.9.5 or 5.5.2.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-75592 being exploited?
There is no known exploitation of CVE-2026-75592 in the wild and no public exploit code.
Sources
Also known as GHSA-6j4c-mgqr-qv76.