CVE-2025-20051

Arbitrary file read via block duplication in Mattermost Boards

Description

Mattermost versions 10.4.x <= 10.4.1, 9.11.x <= 9.11.7, 10.3.x <= 10.3.2, 10.2.x <= 10.2.2 fail to properly validate input when patching and duplicating a board, which allows a user to read any arbitrary file on the system via duplicating a specially crafted block in Boards.

Remediation

Solution:

  • Update Mattermost to versions 10.5.0, 10.4.2, 9.11.8, 10.3.3, 10.2.3 or higher. Alternatively, update the Mattermost Boards plugin to v9.0.5 or higher.

Category

9.9
CVSS
Severity: Critical
CVSS 3.1 •
EPSS 0.10%
Affected: Mattermost Mattermost
Published at:
Updated at:

References

Link Tags
https://mattermost.com/security-updates

Frequently Asked Questions

What is the severity of CVE-2025-20051?
CVE-2025-20051 has been scored as a critical severity vulnerability.
How to fix CVE-2025-20051?
To fix CVE-2025-20051: Update Mattermost to versions 10.5.0, 10.4.2, 9.11.8, 10.3.3, 10.2.3 or higher. Alternatively, update the Mattermost Boards plugin to v9.0.5 or higher.
Is CVE-2025-20051 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-20051 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2025-20051?
CVE-2025-20051 affects Mattermost Mattermost.
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