CVE-2026-27591 (GCVE-0-2026-27591)

Vulnerability from cvelistv5 – Published: 2026-03-11 21:25 – Updated: 2026-03-12 14:23
VLAI?
Title
Winter: Privilege escalation by authenticated backend users
Summary
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.
Severity ?
10 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-284 - Improper Access Control
  • CWE-639 - Authorization Bypass Through User-Controlled Key
  • CWE-915 - Improperly Controlled Modification of Dynamically-Determined Object Attributes
Assigner
References
Impacted products
Vendor Product Version
wintercms winter Affected: >= 1.2.0, < 1.2.12
Affected: >= 1.1.0, < 1.1.12
Affected: < 1.0.477
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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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