CVE-2026-27591

CRITICAL EPSS 38.2%
Published Mar 11, 20263mo ago · Modified Jun 17, 20261w ago
9.9 CVSS 3.1
Critical
Find Similar
Published Mar 11, 2026 3mo ago
Last Modified Jun 17, 2026 1w ago

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 Details

Base Score
9.9
Exploitability
3.1
Impact
6.0
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Changed
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
38.2% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 3

CWE-284
CWE-639
CWE-915

Affected Products 3

VendorProductVersionRange
wintercmswinter* <1.0.477
wintercmswinter*≥1.1.0  –  <1.1.12
wintercmswinter*≥1.2.0  –  <1.2.12

References 4

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

Remediation

  • github.com https://github.com/wintercms/winter/security/advisories/GHSA-pgpf-m8m4-6cg6
    PatchVendor Advisory