CVE-2026-9597

published 2026-07-13

CVE-2026-9597: Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4 fail to verify whether a guest account is deactivated before creating a session in the magic-link token…

Priority P4 29 medium 5.4 CVSS 3.1

AV N AC L PR L UI N S U C L I L A N

Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4 fail to verify whether a guest account is deactivated before creating a session in the magic-link token login path, which allows a deactivated guest user to obtain a fully functional session via a magic-link token issued prior to deactivation.. Mattermost Advisory ID: MMSA-2026-00681

Affected

4 ranges

Vendor	Product	Version range	Fixed in
mattermost	mattermost	11.6.0 – 11.6.4	—
mattermost	mattermost	11.7.0 – 11.7.2	—
mattermost	mattermost_server	>= 11.6.0 < 11.6.5	11.6.5
mattermost	mattermost_server	>= 11.7.0 < 11.7.3	11.7.3

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CWE-305