Mattermost Desktop App versions <=6.2 6.2.2.0 fails to validate the IPC sender in the leaveCall handler which allows a malicious or compromised Mattermost server (or a user with script access to a connected server view) to disconnect an active call belonging to a different connected server via the desktopAPI.leaveCall IPC message. Mattermost Advisory ID: MMSA-2026-00699
References
History

Tue, 13 Oct 2026 12:15:00 +0000

Type Values Removed Values Added
First Time appeared Mattermost mattermost Desktop
CPEs cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*
Vendors & Products Mattermost mattermost Desktop

Thu, 17 Sep 2026 19:45:00 +0000

Type Values Removed Values Added
First Time appeared Mattermost
Mattermost mattermost
Vendors & Products Mattermost
Mattermost mattermost

Thu, 17 Sep 2026 15:30:00 +0000

Type Values Removed Values Added
Description Mattermost Desktop App versions <=6.2 6.2.2.0 fails to validate the IPC sender in the leaveCall handler which allows a malicious or compromised Mattermost server (or a user with script access to a connected server view) to disconnect an active call belonging to a different connected server via the desktopAPI.leaveCall IPC message. Mattermost Advisory ID: MMSA-2026-00699
Title Mattermost Desktop App Missing IPC Sender Validation in Calls Leave Handler
Weaknesses CWE-346
References
Metrics cvssV3_1

{'score': 3.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-09-17T15:11:52.297Z

Updated: 2026-09-17T19:18:45.112Z

Reserved: 2026-06-15T14:05:20.532Z

Link: CVE-2026-12284

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2026-09-17T16:17:21.993

Modified: 2026-10-13T12:04:25.870

Link: CVE-2026-12284

cve-icon Redhat

No data.