CVE-2026-29179: October: Editor Sub-Permission Bypass for Asset and Blueprint File Operations

Published Apr 21, 2026
·
Updated

Fine-grained sub-permission checks for asset and blueprint file operations were not enforced in the CMS and Tailor editor extensions. This only affects backend users who were explicitly granted editor access but had editor.cmsassets or editor.tailorblueprints specifically withheld, an uncommon permission configuration. In this edge case, such users could perform file operations (create, delete, rename, move, upload) on theme assets or blueprint files despite lacking the required sub-permission. A related operator precedence error in the Tailor navigation also disclosed the theme blueprint directory tree under the same conditions.

Impact - Only exploitable by authenticated backend users with editor access who have been specifically denied the editor.cmsassets or editor.tailorblueprints sub-permissions - Does not affect default permission configurations where editor users typically have all sub-permissions granted - Users without editor.cmsassets could manipulate theme asset files (delete, rename, move, upload, create directories) - Users without editor.tailorblueprints could manipulate blueprint files (delete, rename, move, upload, create directories) - Users without editor.tailorblueprints could view the theme blueprint navigation tree, disclosing file paths and directory structure

Patches The vulnerability has been patched in v3.7.16 and v4.1.16. Fine-grained document type permission checks are now enforced on all asset and blueprint file operation commands, and the navigation node condition logic has been corrected. All users are encouraged to upgrade to the latest patched version.

Workarounds - Restrict the editor permission to fully trusted administrators only - Remove the editor permission from any user who should not have asset or blueprint management access

Other sources

October is a Content Management System (CMS) and web platform. Prior to 3.7.16 and 4.1.16, fine-grained sub-permission checks for asset and blueprint file operations were not enforced in the CMS and Tailor editor extensions. This only affects backend users who were explicitly granted editor access but had editor.cmsassets or editor.tailorblueprints specifically withheld, an uncommon permission configuration. In this edge case, such users could perform file operations (create, delete, rename, move, upload) on theme assets or blueprint files despite lacking the required sub-permission. A related operator precedence error in the Tailor navigation also disclosed the theme blueprint directory tree under the same conditions. This vulnerability is fixed in 3.7.16 and 4.1.16.

MITRE

Affected Software

3 affected componentsFixes available
October October CMS<3.7.16, <4.1.16
composer/october/system<3.7.16
3.7.16
composer/october/system>=4.0.0<4.1.16
4.1.16

Event History

Apr 21, 2026
CVE Published
via MITRE·04:19 PM
Data Sourced
via MITRE·04:19 PM
DescriptionSeverityWeakness
Advisory Published
via GitHub·05:15 PM
Data Sourced
via GitHub·05:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via NVD·05:16 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2026-29179?

CVE-2026-29179 is considered to be of high severity due to the potential for unauthorized access to sensitive file operations.

2

How do I fix CVE-2026-29179?

To fix CVE-2026-29179, upgrade to October CMS version 3.7.16 or 4.1.16 or later.

3

What are the risks associated with CVE-2026-29179?

The risks associated with CVE-2026-29179 include unauthorized modification or access to assets and blueprints by users without the necessary permissions.

4

Which versions of October CMS are affected by CVE-2026-29179?

CVE-2026-29179 affects October CMS versions prior to 3.7.16 and 4.1.16.

5

Is CVE-2026-29179 related to any specific features in October CMS?

Yes, CVE-2026-29179 is specifically related to sub-permission checks for asset and blueprint file operations in the October CMS and Tailor editor extension.

Contact

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