CVE-2026-28736

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

03/04/2026

Last modified:

28/04/2026

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&#39;s fileID to read the content of the file. NOTE: Focalboard as a standalone product is not maintained and no fix will be issued.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.30 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): None
Availability (A): None

Base Score 3.x

4.30

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:mattermost:focalboard:8.0.0:::::::*

To consult the complete list of CPE names with products and versions, see this page

References to Advisories, Solutions, and Tools

https://github.com/mattermost-community/focalboard