CVE-2026-27591

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.

Score

CVSS 3.1 10.0 Critical

Status

Analyzed - security-advisories@github.com

Published

2026-03-11

Last modified

2026-03-12

Weaknesses

CWE-284, CWE-639, CWE-915

Affected products

• Winter (Wintercms)

References

• https://github.com/wintercms/winter/security/advisories/GHSA-pgpf-m8m4-6cg6
• https://wintercms.com/releases/v1.0.477
• https://wintercms.com/releases/v1.1.12
• https://wintercms.com/releases/v1.2.12