CVE-2026-9597
Published:July 13, 2026
Updated:July 21, 2026
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 Packages
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.7.0 <v11.7.3Fix Suggestion:
Update to version v11.7.3https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.6.0 <v11.6.5Fix Suggestion:
Update to version v11.6.5github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.6.0 <v11.6.5Fix Suggestion:
Update to version v11.6.5github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.7.0 <v11.7.3Fix Suggestion:
Update to version v11.7.3Related Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.4
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Authentication Bypass by Primary Weakness
EPSS
Base Score:
0.14