PT-2026-30042 · Mattermost · Focalboard

Published 2026-04-03 · Updated 2026-04-03 · CVE-2026-28736

NVD

CVSS v3.1

4.3

Medium

AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

** 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.

Fix

IDOR

Weakness Enumeration

CWE-639

Related Identifiers

CVE-2026-28736

Affected Products

Focalboard

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-28736 · Security Note
• https://github.com/mattermost-community/focalboard · Note
• https://twitter.com/CVEnew/status/2040111911824691675 · Twitter Post
• https://twitter.com/VulmonFeeds/status/2040079259318821284 · Twitter Post