CVE-2026-28736
Focalboard IDOR in file content endpoint allows cross-user file access (unsupported product, no fix)
- State
- Published
- Severity
- 4.3 Medium
- Published
- Apr 3, 2026
- Updated
- Apr 3, 2026
- Reserved
- Apr 3, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.3 Medium | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N | Mattermost |
Weaknesses
- CWE-639 Authorization Bypass Through User-Controlled Key
Affected Products
| Product | Versions |
|---|---|
FocalboardMattermost |
|
References
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