CVE-2026-4643

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

Published: May 18, 2026Updated: Jun 5, 2026 Sources: CVE List NVDCWE-754

3.5LOW

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

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:RUser Interaction

Required

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:LAvailability

Low

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Weaknesses

CWE-754

Affected Products

Mattermost

commercial·US

MattermostOn-premWeb App

Communications / messaging-chat

mattermost desktopOn-premDesktop App

Communications / messaging-chat

Exploitability

Official Patch Available

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References

https://mattermost.com/security-updates

mattermost.com

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