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
Published: 2026-09-17
Score: 3.8 Low
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

Vendor Solution

Update Mattermost Desktop App to versions 6.3.0, 6.2.3.0 or higher.

Tracking

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Advisories

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References
Link Providers
https://mattermost.com/security-updates cve-icon cve-icon
History

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'}

Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: Mattermost

Published:

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

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

Link: CVE-2026-12284

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

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

Modified: 2026-09-17T16:17:21.993

Link: CVE-2026-12284

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses