CVE-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…
Does this matter?
Lower severity and a low EPSS score (0.14%). Track it; it rarely justifies an emergency change on its own.
Description
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
- CVSS 3.1
- 4.6 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
- EPSS
- 0.14% probability · 3th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-829
- Affected
- mattermost/mattermost desktop
- Source
- responsibledisclosure@mattermost.com
References
- https://mattermost.com/security-updatesVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.