Auth bypass in Octobercms October
CVE-2026-29179
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.cms_assets or editor.tailor_blueprints 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.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (12.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001
Affected products
- Octobercms October — versions >= 4.0.0, < 4.1.16, < 3.7.16
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-29179?
- CVE-2026-29179 is a low-severity vulnerability in Octobercms October, classified under Incorrect Authorization. CVSS score: 3.3/10. Published 2026-04-21.
- How severe is CVE-2026-29179?
- Low severity. CVSS v3 base score is 3.3 out of 10.