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
References (1)
Scores
CVSS v3
4.6
EPSS
0.0003
EPSS Percentile
9.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-829
Status
published
Products (1)
mattermost/mattermost_desktop
< 5.13.4
Published
Mar 02, 2026
Tracked Since
Mar 02, 2026