CVE-2026-107844 Contao: Path traversal in the images controller
Unauthenticated attackers can read arbitrary files within the project directory and disclose filesystem paths via path traversal in the images controller.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-107844?
CVE-2026-107844 is a medium-severity path traversal vulnerability in contao, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Contao is an Open Source CMS. From version 5.0.0 until 5.3.50 and 5.7.12, ImagesController joins the user-controlled {path} parameter to the configured image target directory with Path::join() but does not use Path::isBasePath() to verify that the canonical path remains inside that directory. An unauthenticated request containing encoded parent-directory segments can therefore return files under the project directory through BinaryFileResponse when their names use an extension allowed by contao.image.valid_extensions. The route can also reveal whether arbitrary paths exist, and debug responses can disclose absolute filesystem paths, but paths below the upload directory were not shown to be readable. This issue is fixed in versions 5.3.50 and 5.7.12.
Weakness: CWE-22
Which versions are affected by CVE-2026-107844?
4 open source packages ship an affected version, including contao/core-bundle.
| Package | Affected | Fixed in |
|---|---|---|
contao/core-bundle Packagist | From 4.1.0 | 5.3.50 |
contao/core-bundle Packagist | From 4.1.0 | 5.3.50 |
contao/core-bundle Packagist | From 5.4.0-RC1 | 5.7.12 |
contao/core-bundle Packagist | From 5.4.0-RC1 | 5.7.12 |
How do I fix CVE-2026-107844?
Upgrade contao/core-bundle to a fixed version for your release line: 5.3.50 or 5.7.12.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-107844 being exploited?
There is no known exploitation of CVE-2026-107844 in the wild and no public exploit code.
Sources
Also known as GHSA-mrvp-7wmx-5m4h.