MEDIUM · 5.4

CVE-2026-16044

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest ...

Vulnerability Description

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest user to Board Admin via importing a crafted .boardarchive file. Mattermost Advisory ID: MMSA-2026-00672

CVSS Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW

Affected Products

VendorProductVersions
MattermostMattermost Server>= 10.11.0, < 10.11.22

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-16044?

CVE-2026-16044 is a vulnerability with a CVSS score of 5.4 (MEDIUM). Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest ...

How severe is CVE-2026-16044?

CVE-2026-16044 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-16044?

Check the references section above for vendor advisories and patch information. Affected products include: Mattermost Mattermost Server.