Denial of Service Vulnerability in Mattermost Desktop App

CVE-2026-4643

What is CVE-2026-4643?

The Mattermost Desktop App is affected by a vulnerability that allows a malicious server or plugin to exploit server-rendered content management. This issue arises when the app fails to prevent the closure of underlying application views. An attacker can invoke the {{window.close()}} command within the renderer context, leading to a denial of service condition at the client level. This can significantly disrupt users' ability to utilize the Mattermost client effectively, potentially halting their operations until the issue is resolved. It is crucial for users of affected versions to ensure they apply the latest security updates.

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