CVE-2026-55850Element Web: A malicious homeserver can inject HTML in Element Web using its homepage

Descripción

Element Web is a Matrix web client built using the Matrix React SDK. Prior to 1.12.22, EmbeddedPage in apps/web/src/components/structures/EmbeddedPage.tsx renders homeserver-supplied homepage content through dangerouslySetInnerHTML without passing it through sanitizedHtmlNode. A malicious homeserver can provide crafted HTML that Element Web renders on the homepage; the content security policy prevents JavaScript but not phishing HTML. This issue is fixed in version 1.12.22.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• https://github.com/element-hq/element-web/security/advisories/GHSA-wrcp-5v3v-3j6v
• https://github.com/element-hq/element-web/commit/7949980a7e3c7e397d7afe899ef1b0563c417b0e
• https://github.com/element-hq/element-web/releases/tag/v1.12.22
• https://www.machinespirits.com/advisory/563a17