CVE-2026-55850 — Element Web: A malicious homeserver can inject HTML in Element Web using its homepage
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-sup…
Published: 2026-08-21 · CVSS: 5.3 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7