Mattermost up to 9.11.17/10.5.8/10.8.3/10.9.2 path traversal

Summaryinfo

A vulnerability marked as critical has been reported in Mattermost up to 9.11.17/10.5.8/10.8.3/10.9.2. Impacted is an unknown function. Performing a manipulation results in path traversal. This vulnerability is cataloged as CVE-2025-8023. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mattermost up to 9.11.17/10.5.8/10.8.3/10.9.2. It has been classified as problematic. This affects an unknown code. The manipulation with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. This is going to have an impact on confidentiality. The summary by CVE is:

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2 fails to sanitize path traversal sequences in template file destination paths, which allows a system admin to perform path traversal attacks via malicious path components, potentially enabling malicious file placement outside intended directories.

The weakness was shared by Dawid Kulikowski. It is possible to read the advisory at mattermost.com. This vulnerability is uniquely identified as CVE-2025-8023 since 07/22/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1006 according to MITRE ATT&CK.

Upgrading to version 9.11.18, 10.5.9, 10.8.4, 10.9.3 or 10.10.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at EUVD (EUVD-2025-25412) and CERT Bund (WID-SEC-2025-1625). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Mattermost Mattermost

Productinfo

Type

• Groupware Software

Name

• Mattermost

Version

• 9.11.0
• 9.11.1
• 9.11.2
• 9.11.3
• 9.11.4
• 9.11.5
• 9.11.6
• 9.11.7
• 9.11.8
• 9.11.9
• 9.11.10
• 9.11.11
• 9.11.12
• 9.11.13
• 9.11.14
• 9.11.15
• 9.11.16
• 9.11.17
• 10.5.0
• 10.5.1
• 10.5.2
• 10.5.3
• 10.5.4
• 10.5.5
• 10.5.6
• 10.5.7
• 10.5.8
• 10.8.0
• 10.8.1
• 10.8.2
• 10.8.3
• 10.9.0
• 10.9.1
• 10.9.2

License

• open-source

CPE 2.3info

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CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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