CVE-2026-1628
Mattermost allows external websites to open within the app, exposing preload functionality to non-trusted sites.
Summary
Mattermost allows external websites to open within the app, exposing preload functionality to non-trusted sites.
Original description
The description as published by the source.
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
References
- advisory github.com
- advisory mattermost.com
- advisory nvd.nist.gov