CVE-2026-28741: CSRF Protection Bypass Allows Updating a User's Authentication Method

Published Apr 15, 2026
·
Updated

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 Software

5 affected components
Mattermost Mattermost>=10.11.0<=10.11.12, =11.5.0, >=11.4.0<=11.4.2, >=11.3.0<=11.3.2
Mattermost Mattermost Server>=10.11.0<10.11.13
Mattermost Mattermost Server>=11.3.0<11.3.3
Mattermost Mattermost Server>=11.4.0<11.4.3
Mattermost Mattermost Server>=11.5.0<11.5.1

Remediation

Information

Update Mattermost to versions 10.11.13, 11.5.1, 11.4.3, 11.3.3 or higher.

Event History

Apr 15, 2026
CVE Published
via MITRE·10:13 AM
Data Sourced
via MITRE·10:13 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·11:16 AM
DescriptionSeverityWeaknessAffected Software
May 23, 58277
Event
via NVD·08:43 AM

Frequently Asked Questions

1

What is the severity of CVE-2026-28741?

CVE-2026-28741 is classified as a medium severity vulnerability due to its potential impact on user security.

2

How do I fix CVE-2026-28741?

To fix CVE-2026-28741, users should upgrade their Mattermost installation to a version that addresses the CSRF protection bypass.

3

What versions are affected by CVE-2026-28741?

CVE-2026-28741 affects Mattermost versions 10.11.0 to 10.11.12, 11.4.0 to 11.4.2, 11.3.0 to 11.3.2, and exactly 11.5.0.

4

What are the potential consequences of CVE-2026-28741?

If exploited, CVE-2026-28741 allows an attacker to potentially change a user's authentication method, leading to unauthorized access.

5

Is there a workaround for CVE-2026-28741?

There is no official workaround for CVE-2026-28741; the recommended action is to upgrade to a patched version of Mattermost.

Contact

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