CVE-2026-125338
Received Received - Intake

Stored XSS in Winter CMS via Unsanitized CSS Cache

Vulnerability report for CVE-2026-125338, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-11-10

Last updated on: 2026-11-10

Assigner: GitHub, Inc.

Description

Winter CMS is a content management system built on the Laravel PHP framework. Prior to 1.2.14, BrandSetting::renderCss() and EditorSetting::renderCss() store raw LESS compiler output with Cache::forever() but apply strip_tags() only to the value returned on a cache miss. The first render after saving custom CSS appears sanitized while priming an unsafe cache entry, and later cache hits return unsanitized output into the backend style element, allowing a user with backend.manage_branding or backend.manage_editor to cause stored cross-site scripting when another backend page renders the styles. The styles also appear on unauthenticated backend sign-in, password restore, and password reset layouts. This issue is fixed in version 1.2.14.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-11-10
Last Modified
2026-11-10
Generated
2026-11-10
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
winter_cms winter_cms 1.2.14

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-79 The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
AI Quick Actions have not been generated yet.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-125338. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart

Security Radar

News mentioning this vulnerability
Loading related security news...