CVE-2026-126662
Contao 4.0.0 before 5.3.54, 5.4.0 before 5.7.17, and 6.0.0 before 6.0.6 Filemount Bypass via Edit-Multiple
Contao 4.0.0 before 5.3.54, 5.4.0 before 5.7.17, and 6.0.0 before 6.0.6 contains an access control bypass vulnerability that allows filemount-restricted backend users to modify folders outside their filemount via the file manager Edit-Multiple operation. Attackers holding the protected or syncExclude field permission can submit outside folder paths in the IDS parameter to publish protected folders or exclude them from DBAFS synchronization, exposing files for public download.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| Contao Contao contao/core-bundle
composer |
≥ 4.0.0; < 5.3.54 (affected, semver) ≥ 5.4.0-RC1; < 5.7.17 (affected, semver) ≥ 6.0.0-RC1; < 6.0.6 (affected, semver) Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 7.1 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N | CNA: VulnCheck |
| 3.1 / 7.1 high |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N | CNA: VulnCheck |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/contao/contao/security/advisories/GHSA-9jfh-v443-w3fjCNA: VulnCheck · vendor-advisory
- https://github.com/contao/contao/commit/c01898f99c5d5af50a227ee85f27270c5427f900CNA: VulnCheck · patch
- https://github.com/contao/contao/commit/a104202df2b532bb64805a0856fc94bb0bddbb66CNA: VulnCheck · patch
- https://github.com/contao/contao/commit/240e169441796bb703819ee0e22728708f946b70CNA: VulnCheck · patch
- https://github.com/contao/contao/releases/tag/5.3.54CNA: VulnCheck · release-notes
- https://github.com/contao/contao/releases/tag/5.7.17CNA: VulnCheck · release-notes
- https://github.com/contao/contao/releases/tag/6.0.6CNA: VulnCheck · release-notes
- https://github.com/contao/contao/blob/5.3.53/core-bundle/contao/drivers/DC_Folder.php#L1716-L1720CNA: VulnCheck · technical-description
- https://www.vulncheck.com/advisories/contao-4.0.0-before-5.3.54-5.4.0-before-5.7.17-and-6.0.0-before-6.0.6-filemount-bypass-via-edit-multipleCNA: VulnCheck · third-party-advisory
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