Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owne…

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

1. Jul 17, 2026 · NIST NVD

   Detected

   Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owner to crash the Mattermost Desktop App via changing the payload of a method to a malformed one. Mattermost Advisory ID: MMSA-2026-00678

2. Oct 15, 2026 · NIST NVD

   Updated

   Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owner to crash the Mattermost Desktop App via changing the payload of a method to a malformed one. Mattermost Advisory ID: MMSA-2026-00678

Affected

• cpe mattermost/mattermost desktopversion unspecified

Sources

• CVE.orgVulnerability recordCVE-2026-9602

  Official CVE identifier

  cve.org
• FIRST EPSSExploitation probabilityCVE-2026-9602

  30-day exploitation probability 0.4%

  first.org
• NIST NVDVulnerability recordCVE-2026-9602

  Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owner to crash the Mattermost Desktop App via changing the payload of a method to a malformed one. Mattermost Advisor

  nvd.nist.gov

References

• Vendor Advisory · mattermost.com