CVE-2026-27591
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.49%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 9.9 CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 0.49% probability · 40th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-284, CWE-639, CWE-915
- Affected
- wintercms/winter
- Source
- security-advisories@github.com
References
- https://github.com/wintercms/winter/security/advisories/GHSA-pgpf-m8m4-6cg6Patch, Vendor 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.