CVE-2026-16044 — Insufficient validation of guest board admin privileges on archive import

CVE-2026-16044

Insufficient validation of guest board admin privileges on archive import PUBLISHED

Description (CNA)

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

Affected (CNA)

Vendor / product	Versions
Mattermost / Mattermost	affected 11.7.0 through 11.7.6; affected 10.11.0 through 10.11.21; unaffected 11.9.0; unaffected 11.7.7; unaffected 10.11.22

CWE

CWE-863

References

https://mattermost.com/security-updates

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.