ZDF
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2026-27591

Winter is a free, open-source content management system (CMS) based on the Laravel PHP framework.

Published Mar 11, 2026 · catalog updated Jun 17, 2026 · Winter is a free,

Check if you run it

No confirmed exploitation is on record for CVE-2026-27591. EPSS is 0.86%. Act only if a listed version of Winter is a free, is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (Winter is a free,).
  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Critical9.9
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.86%
Remediation
Advisory link
Affected products
cpe wintercms/winter

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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe wintercms/winterversion unspecified

How to fix CVE-2026-27591

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-27591. EPSS is 0.86%. Act only if a listed version of Winter is a free, is installed.

Which versions are affected?

Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-284: Improper Access Control; CWE-639: Authorization Bypass Through User-Controlled Key; CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes. EPSS 0.86%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Mar 11, 2026 · NIST NVD

    Detected

    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 secur

  2. Jun 17, 2026 · NIST NVD

    Updated

    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 secur

Sources

  • CVE.orgVulnerability recordCVE-2026-27591

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-27591

    30-day exploitation probability 0.9%

    first.org
  • NIST NVDVulnerability recordCVE-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 ass

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.