CVE-2026-28736
Medium
Description
** UNSUPPORTED WHEN ASSIGNED ** Focalboard version 8.0 fails to validate file ownership when serving uploaded files. This allows an authenticated attacker who knows a victim's fileID to read the content of the file. NOTE: Focalboard as a standalone product is not maintained and no fix will be issued.
SeverityMedium
CVSS4.3
Exploit probability—
Product
Mattermost Focalboard
PublishedApr 3, 2026
First seenApr 3, 2026
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost focalboard | 8.0.0 | — |
| github.com/mattermost/focalboardGo | v ≤ 7.10.6, No range specified | — |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.