Auth bypass in Craftcms Cms
CVE-2026-33159
Craft CMS is a content management system (CMS). From version 4.0.0-RC1 to before version 4.17.8 and from version 5.0.0-RC1 to before version 5.9.14, guest users can access Config Sync updater index, obtain signed data, and execute state-changing Config Sync actions (regenerate-yaml, apply-yaml-changes) without authentication. This issue has been patched in versions 4.17.8 and 5.9.14.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (35.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 35th percentile — 35.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
- Craftcms Cms — versions >= 4.0.0-RC1, < 4.17.8, >= 5.0.0-RC1, < 5.9.14
- Craftcms Craft Cms — versions 4.0.0, 5.0.0
Weakness classification (CWE)
References
- github.com/craftcms/cms/security/advisories/GHSA-6mrr-q3pj-h53w (Vendor Advisory)
- github.com/craftcms/cms/commit/7f0ead833f7c2b91ae12003caad833479dd08592 (Patch)
- github.com/craftcms/cms/releases/tag/4.17.8 (Release Notes)
- github.com/craftcms/cms/releases/tag/5.9.14 (Release Notes)
Frequently asked questions
- What is CVE-2026-33159?
- CVE-2026-33159 is a medium-severity vulnerability in Craftcms Cms, classified under Missing Authentication for Critical Function. CVSS score: 6.5/10. Published 2026-03-24.
- How severe is CVE-2026-33159?
- Medium severity. CVSS v3 base score is 6.5 out of 10.