CVE-2026-28736 (GCVE-0-2026-28736)
Vulnerability from cvelistv5 – Published: 2026-04-03 13:25 – Updated: 2026-04-03 14:54 Unsupported When Assigned
VLAI
EPSS
VEX
Title
Focalboard IDOR in file content endpoint allows cross-user file access (unsupported product, no fix)
Summary
** 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.
Severity
4.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-03 14:53 UTC
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/mattermost-community/focalboard | product |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Mattermost | Focalboard |
Affected:
0 , ≤ 8.0
(semver)
|
guessed |
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