LOW · 3.1

CVE-2026-55825

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 attach...

Vulnerability 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.

CVSS Score

3.1

LOW

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-55825?

CVE-2026-55825 is a vulnerability with a CVSS score of 3.1 (LOW). 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 attach...

How severe is CVE-2026-55825?

CVE-2026-55825 has been rated LOW with a CVSS base score of 3.1/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-55825?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.