CVE-2026-55850

Element Web: A malicious homeserver can inject HTML in Element Web using its homepage

Published: Aug 21, 2026Updated: Aug 21, 2026 Sources: CVE List NVDCWE-79

N/ACVSS

NVD MITRE

Description

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.

No summary for this CVE yet.

Weaknesses

CWE-79

Affected Products

element-hq

oss-project

element-webMixed

Communications / messaging-chat

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Execution

Initial Access

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References

https://github.com/element-hq/element-web/commit/7949980a7e3c7e397d7afe899ef1b0563c417b0e

github.com

https://github.com/element-hq/element-web/releases/tag/v1.12.22

github.com

https://github.com/element-hq/element-web/security/advisories/GHSA-wrcp-5v3v-3j6v

github.com

and 1 more references View all →

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