CVE-2026-84371 (GCVE-0-2026-84371)

Vulnerability from cvelistv5 – Published: 2026-09-01 20:51 – Updated: 2026-09-02 16:02
VLAI
Title
ApostropheCMS: Stored XSS via SVG SMIL URI-list scheme-policy bypass
Summary
ApostropheCMS is an open-source Node.js content management system, and sanitize-html provides a simple HTML sanitizer with a clear API. From version 1.9.0 until version 2.17.7, packages/sanitize-html/index.js validates an animation value attribute as one flat URL and does not recognize that attributeName selecting href or xlink:href gives the sibling values, from, to, or by attribute SVG SMIL URL semantics. In configurations that allow the animate, animateColor, animateMotion, animateTransform, or set elements, a values list can begin with a safe fragment and contain a later executable destination that survives allowedSchemesAppliedToAttributes checking. When the sanitized SVG is rendered, the browser can copy that later destination into the live link, and a victim who activates the link can execute script in the application's origin. This issue is fixed in version 2.17.7.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-02 13:42 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7643 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
apostrophecms apostrophe Affected: >= 1.9.0, < 2.17.7
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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