Wn backend module: Winter: Stored XSS through Brand Settings custom styles (CVE-2026-32257)
Winter CMS backend module versions prior to 1.2.13 have a stored cross-site scripting (XSS) vulnerability in the Brand Settings custom styles feature. This flaw allows users with the backend.manage_branding permission to inject malicious CSS that is compiled and rendered on every backend page without proper sanitization. The vulnerability requires trusted backend access with specific administrative permissions, which limits its severity. The issue is patched in version 1.2.13.
AI Analysis
Technical Summary
The Winter CMS backend module contains a stored XSS vulnerability (CVE-2026-32257) in the Brand Settings custom styles feature. Users with the backend.manage_branding permission can inject malicious CSS that is compiled and rendered on all backend pages without adequate sanitization. This vulnerability affects versions prior to 1.2.13 and has been fixed in 1.2.13. Exploitation requires high privileges and user interaction, reducing the risk scope.
Potential Impact
Successful exploitation allows an attacker with backend.manage_branding permission to execute arbitrary code in the context of the backend interface by injecting malicious CSS. This can lead to compromise of confidentiality and integrity of backend operations. However, the requirement for trusted backend access and specific permissions limits the attacker's ability to exploit this vulnerability remotely or by unprivileged users.
Mitigation Recommendations
Upgrade Winter CMS backend module to version 1.2.13 or later, where this vulnerability is patched. Since a patch is available, applying the official fix is the recommended remediation.
Wn backend module: Winter: Stored XSS through Brand Settings custom styles (CVE-2026-32257)
Description
Winter CMS backend module versions prior to 1.2.13 have a stored cross-site scripting (XSS) vulnerability in the Brand Settings custom styles feature. This flaw allows users with the backend.manage_branding permission to inject malicious CSS that is compiled and rendered on every backend page without proper sanitization. The vulnerability requires trusted backend access with specific administrative permissions, which limits its severity. The issue is patched in version 1.2.13.
CVSS v3.1
Score 8.1high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Winter CMS backend module contains a stored XSS vulnerability (CVE-2026-32257) in the Brand Settings custom styles feature. Users with the backend.manage_branding permission can inject malicious CSS that is compiled and rendered on all backend pages without adequate sanitization. This vulnerability affects versions prior to 1.2.13 and has been fixed in 1.2.13. Exploitation requires high privileges and user interaction, reducing the risk scope.
Potential Impact
Successful exploitation allows an attacker with backend.manage_branding permission to execute arbitrary code in the context of the backend interface by injecting malicious CSS. This can lead to compromise of confidentiality and integrity of backend operations. However, the requirement for trusted backend access and specific permissions limits the attacker's ability to exploit this vulnerability remotely or by unprivileged users.
Mitigation Recommendations
Upgrade Winter CMS backend module to version 1.2.13 or later, where this vulnerability is patched. Since a patch is available, applying the official fix is the recommended remediation.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-v7cf-8gh9-gxmj
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-32257"]
- Ecosystems
- ["Packagist"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a7c9b39bf8831d539cdc775
Added to database: 08/12/2026, 16:11:37 UTC
Last enriched: 09/12/2026, 05:18:04 UTC
Last updated: 09/25/2026, 01:47:42 UTC
Views: 38
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