Description
Mattermost Desktop App versions <=6.2 5.5.13 6.0.2.0 fail to properly null check when checking for headers in the Mattermost Desktop App which allows any user to crash another channel members Desktop App via posting a malicious link with an embedded image that misses one of those headers. Mattermost Advisory ID: MMSA-2026-00668
Affected products
mattermost: mattermost desktop
References1
- mattermost.com/security-updates Vendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 37 · as of 15 November 2026
- CWE
- CWE-754
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