CVE-2016-9554

/// Technical description

The Sophos Web Appliance Remote / Secure Web Gateway server (version 4.2.1.3) is vulnerable to a Remote Command Injection vulnerability in its web administrative interface. These vulnerabilities occur in MgrDiagnosticTools.php (/controllers/MgrDiagnosticTools.php), in the component responsible for performing diagnostic tests with the UNIX wget utility. The application doesn't properly escape the information passed in the 'url' variable before calling the executeCommand class function ($this->dtObj->executeCommand). This function calls exec() with unsanitized user input allowing for remote command injection. The page that contains the vulnerabilities, /controllers/MgrDiagnosticTools.php, is accessed by a built-in command answered by the administrative interface. The command that calls to that vulnerable page (passed in the 'section' parameter) is: 'configuration'. Exploitation of this vulnerability yields shell access to the remote machine under the 'spiderman' user account.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References