CVE-2026-55825 Contao: Possible path traversal in job download URIs
Authenticated backend users can read files from other job directories via path traversal in attachment URIs, bypassing cross-job authorization.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-55825?
CVE-2026-55825 is a low-severity path traversal vulnerability in contao, published on 31 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Contao is an Open Source CMS. In versions 5.7.0 through 5.7.6, an authenticated backend user who can access one job can request an attachment identifier containing ../ segments and make the job attachment download endpoint read a file from another job directory inside var/job-attachments. The controller authorizes only the jobUuid route parameter. The later attachment lookup joins that authorized job UUID with the attacker-controlled identifier, then passes the combined path to the virtual filesystem. VirtualFilesystem::resolve() canonicalizes the whole path and only rejects paths that escape the filesystem mount, so authorized-job/../victim-job/debug_log.csv becomes victim-job/debug_log.csv. This is a cross-job authorization bypass for known job attachment paths. It is not a practical brute-force against unknown jobs because job directories are UUID v4 values.
Weakness: CWE-22
Which versions are affected by CVE-2026-55825?
4 open source packages ship an affected version, including contao/contao and contao/core-bundle.
| Package | Affected | Fixed in |
|---|---|---|
contao/contao Packagist | From 5.7.0 | 5.7.7 |
contao/contao Packagist | From 5.7.0 | 5.7.7 |
contao/core-bundle Packagist | From 5.7.0 | 5.7.7 |
contao/core-bundle Packagist | From 5.7.0 | 5.7.7 |
How do I fix CVE-2026-55825?
Upgrade contao/contao to 5.7.7 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-55825 being exploited?
There is no known exploitation of CVE-2026-55825 in the wild and no public exploit code.
Sources
Also known as GHSA-grm4-wm43-9jh5.