Bug 2451775 (CVE-2026-3113)

Summary: CVE-2026-3113 Mattermost: Mattermost: Information disclosure via improper permissions on bulk exports
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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. The system fails to properly set file permissions on downloaded bulk exports. This vulnerability allows other local users on the server to read the sensitive contents of these bulk export files, leading to unauthorized information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-03-26 17:01:48 UTC
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to set permissions on downloaded bulk export which allows other local users on the server to be able to read contents of the bulk export.. Mattermost Advisory ID: MMSA-2026-00593