CVE-2026-28741

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

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://mattermost.com/security-updates	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::

History

22 Apr 2026, 19:42

Type	Values Removed	Values Added
First Time		Mattermost Mattermost mattermost Server
CPE		cpe:2.3:a:mattermost:mattermost_server::::::::
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory

15 Apr 2026, 11:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-15 11:16

Updated : 2026-04-22 19:42

NVD link : CVE-2026-28741

Mitre link : CVE-2026-28741

CVE.ORG link : CVE-2026-28741

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-352

Cross-Site Request Forgery (CSRF)

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