CVE-2026-4643lowCWE-754

CVE-2026-4643: low-severity vulnerability in Mattermost

Calling window.close() from server-side content causes crash in the Mattermost Desktop App

Published

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 3.5epss 0.2%
Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent server-rendered content from closing an underlying application view in the Mattermost Desktop App which allows a malicious server or plugin to crash the desktop client via invoking {{window.close()}} in the renderer context, leading to a denial of service condition at the client level. Mattermost Advisory ID: MMSA-2026-00633
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L
Affected products
Mattermost · Mattermost
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