Vulnerability Description
Winter is a free, open-source content management system (CMS) based on the Laravel PHP framework. Prior to 1.0.477, 1.1.12, and 1.2.12, Winter CMS allowed authenticated backend users to escalate their accounts level of access to the system by modifying the roles / permissions assigned to their account through specially crafted requests to the backend while logged in. To actively exploit this security issue, an attacker would need access to the Backend with a user account with any level of access. This vulnerability is fixed in 1.0.477, 1.1.12, and 1.2.12.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Wintercms | Winter | < 1.0.477 |
Related Weaknesses (CWE)
References
- https://github.com/wintercms/winter/security/advisories/GHSA-pgpf-m8m4-6cg6PatchVendor Advisory
- https://wintercms.com/releases/v1.0.477Release Notes
- https://wintercms.com/releases/v1.1.12Release Notes
- https://wintercms.com/releases/v1.2.12Release Notes
FAQ
What is CVE-2026-27591?
CVE-2026-27591 is a vulnerability with a CVSS score of 9.9 (CRITICAL). Winter is a free, open-source content management system (CMS) based on the Laravel PHP framework. Prior to 1.0.477, 1.1.12, and 1.2.12, Winter CMS allowed authenticated backend users to escalate their...
How severe is CVE-2026-27591?
CVE-2026-27591 has been rated CRITICAL with a CVSS base score of 9.9/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-27591?
Check the references section above for vendor advisories and patch information. Affected products include: Wintercms Winter.