Bug 2458652 (CVE-2026-28741)

Summary: CVE-2026-28741 mattermost: CSRF protection bypass allows updating a user's authentication method
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Mattermost. Improper validation of CSRF tokens on an authentication endpoint allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2458722, 2458723    
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Description OSIDB Bzimport 2026-04-15 11:01:27 UTC
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