CVE-2026-12284
3.7 · LOWMattermost 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…
Overview
CVE-2026-12284 is a low-severity vulnerability affecting mattermost mattermost_desktop. It was published on September 17, 2026 and has a CVSS 3.1 base score of 3.7 (LOW).
This vulnerability has a CVSS 3.1 base score of 3.7, rated LOW. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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
Remediation
Check the references section for vendor advisories and patches from mattermost. Update mattermost_desktop to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mattermost | mattermost_desktop | >= 6.2.0, < 6.2.3 | Affected |
References
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Frequently asked questions
What is CVE-2026-12284?
CVE-2026-12284 is a low-severity vulnerability affecting mattermost mattermost_desktop. It was published on September 17, 2026 and has a CVSS 3.1 base score of 3.7 (LOW).
How severe is CVE-2026-12284?
This vulnerability has a CVSS 3.1 base score of 3.7, rated LOW. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-12284?
Check the references section for vendor advisories and patches from mattermost. Update mattermost_desktop to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-12284?
CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-12284 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.
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