CVE-2026-55850

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.

CVSS

No CVSS.

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-21 19:17

Updated : 2026-08-21 20:16

NVD link : CVE-2026-55850

Mitre link : CVE-2026-55850

CVE.ORG link : CVE-2026-55850

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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