Bug 2451791 (CVE-2026-3112)

Summary: CVE-2026-3112 Mattermost: Mattermost: Information Disclosure via Advanced Logging file target path validation bypass
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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OS: Linux   
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A flaw was found in Mattermost. This vulnerability allows a system administrator to read arbitrary files on the host system. This is possible due to a failure to properly validate Advanced Logging file target paths, which can be exploited by providing a malicious AdvancedLoggingJSON configuration during support packet generation. This could lead to the disclosure of sensitive information.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-03-26 17:02:53 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 validate Advanced Logging file target paths which allows system administrators to read arbitrary host files via malicious AdvancedLoggingJSON configuration in support packet generation. Mattermost Advisory ID: MMSA-2025-00562