CVE-2026-4643

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

Published May 18, 2026 CVSS 3.1 · 3.5 Low EPSS < 1% KEV · Not listed
Description
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

Remediation

Vendor Solution

Update Mattermost Desktop App to versions 6.2.0, 6.1.1.0, 5.13.5.0 or higher.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
References
History
Type Values Removed Values Added
First Time appeared Mattermost mattermost Desktop
CPEs cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*
Vendors & Products Mattermost mattermost Desktop
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Mattermost
Mattermost mattermost
Vendors & Products Mattermost
Mattermost mattermost
Type Values Removed Values Added
Description 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
Title Calling window.close() from server-side content causes crash in the Mattermost Desktop App
Weaknesses CWE-754
References
Metrics cvssV3_1

{'score': 3.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Mattermost
Published
Updated
May 18, 2026, 2:36 PM
Reserved
Mar 23, 2026, 11:42 AM
Status
Analyzed
Published
May 18, 2026, 9:16 AM
Modified
Jun 17, 2026, 10:56 AM