CVE-2026-12284 (GCVE-0-2026-12284)

Vulnerability from cvelistv5 – Published: 2026-09-17 15:11 – Updated: 2026-09-17 19:18
VLAI
Title
Mattermost Desktop App Missing IPC Sender Validation in Calls Leave Handler
Summary
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
Severity
3.8 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 19:18 UTC
CWE
  • CWE-346 - Origin Validation Error
Assigner
Mattermost CNA under the mitre root
CNA scorecard B 80/100 over 107 records in the last 180 days details
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 0 , ≤ 6.2.2 (semver)
Unaffected: 6.3.0
Unaffected: 6.2.3.0
guessed Create a notification for this product.
Credits
Juho Forsén
Show details on NVD website
To clipboard 

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