CVE-2026-28741
Published:April 15, 2026
Updated:May 18, 2026
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page. Mattermost Advisory ID: MMSA-2026-00625
Affected Packages
github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.4.0 <v11.4.3Fix Suggestion:
Update to version v11.4.3github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.3.0 <v11.3.3Fix Suggestion:
Update to version v11.3.3github.com/mattermost/mattermost (GO):
Affected version(s) >=v10.11.0 <v10.11.13Fix Suggestion:
Update to version v10.11.13github.com/mattermost/mattermost (GO):
Affected version(s) =v11.5.0 <v11.5.1Fix Suggestion:
Update to version v11.5.1github.com/mattermost/mattermost/server/v8 (GO):
Affected version(s) >=v8.0.0-20250721062209-4952acea88ce <v8.0.0-20260220133927-c29cf05d40f8Fix Suggestion:
Update to version v8.0.0-20260220133927-c29cf05d40f8Related Resources (3)
Do you need more information?
Contact UsCVSS v4
Base Score:
7.6
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
PASSIVE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.8
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Cross-Site Request Forgery (CSRF)
EPSS
Base Score:
0.02