cyfenced.com →

[ CVE-2026-112951 · Published 20 Oct 2026 ]

ApostropheCMS: Color field validation bypass allows stored XSS via HTML appended after rgb()/hsl() prefix

CVSS 5.4 EPSS <1%Fix available

[ Why it matters ]Priority signals

  • Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

ApostropheCMS is an open-source Node.js content management system. Prior to 4.34.0, the color field accepts trailing content after a valid rgb() or hsl() prefix because its TinyColor validation does not require the entire value to match a color. An authenticated user with edit rights can store arbitrary HTML after a valid color prefix. When the stored value is rendered, the payload executes, resulting in stored XSS. This issue is fixed in version 4.34.0.

[ Fixes ]Fixes and patches

  • apostrophe 4.34.0Fixed version · GitHub Advisories · npm package apostrophe: upgrade to 4.34.0 or later (affected < 4.34.0)

[ Packages ]Affected open-source packages

[ References ]References