Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to…

Code

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Timeline

Detection, updates, and resolution for this record.

1. Mar 2, 2026 · NIST NVD

   Detected

   Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Mattermost server. Mattermost Advisory ID: MMSA-2026-00596

2. Jun 17, 2026 · NIST NVD

   Updated

   Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Mattermost server. Mattermost Advisory ID: MMSA-2026-00596

Affected

• cpe mattermost/mattermost desktopversion unspecified

Sources

• NIST NVDVulnerability recordCVE-2026-1628

  Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Matter

  nvd.nist.gov

References

• Vendor Advisory · mattermost.com