CVE-2025-13870: Unauthorized access and subscription vulnerability in Boards

Published Dec 2, 2025
·
Updated

Mattermost versions 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to validate the user permission when accessing the files and subscribing to the block in Boards, which allows an authenticated user to access other board files and was able to subscribe to the block from other boards that the user does not have access to

Affected Software

6 affected componentsFixes available
Mattermost Mattermost<=10.11.4, <=10.5.12
go/github.com/mattermost/mattermost>=10.5.0<10.5.13
10.5.13
go/github.com/mattermost/mattermost>=10.11.0<10.11.5
10.11.5
go/github.com/mattermost/mattermost/server/v8<8.0.0-20250905150616-ba86dfc5876b
8.0.0-20250905150616-ba86dfc5876b
Mattermost Mattermost Server>=10.5.0<10.5.13
Mattermost Mattermost Server>=10.11.0<10.11.5

Remediation

Information

Update Mattermost to versions 11.1.0, 10.11.5, 10.5.13 or higher.

Event History

Dec 2, 2025
CVE Published
via MITRE·09:28 AM
Data Sourced
via MITRE·09:28 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·10:16 AM
DescriptionSeverityWeaknessAffected Software
Advisory Published
via GitHub·12:30 PM
Data Sourced
via GitHub·12:30 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-13870?

The severity of CVE-2025-13870 is classified as medium due to potential unauthorized access to sensitive information.

2

How do I fix CVE-2025-13870?

To fix CVE-2025-13870, upgrade your Mattermost installation to version 10.11.5 or 10.5.13 or later.

3

Who is affected by CVE-2025-13870?

CVE-2025-13870 affects Mattermost versions 10.11.x up to 10.11.4 and 10.5.x up to 10.5.12.

4

What type of vulnerability is CVE-2025-13870?

CVE-2025-13870 is a permission validation vulnerability that allows authenticated users to access unauthorized files.

5

Is there a workaround for CVE-2025-13870 if an upgrade is not possible?

There are no official workarounds for CVE-2025-13870, and upgrading to a secure version is strongly recommended.

Contact

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