whmcs mail system review

I am looking for an experienced freelancer to provide an in-depth security review of my WHMCS mail system. The review should be conducted on a live server, and will require root access. The review should focus on the security aspects of the system, and the freelancer should be knowledgeable on the requirements for a secure mail system. In order to complete the audit, the freelancer should perform a comprehensive analysis of the system, checking for any potential vulnerabilities. The freelancer should then provide a detailed report of their findings, outlining any security concerns and recommending solutions to strengthen the system. Once the report is complete, the freelancer should be available to discuss their findings and provide any necessary support.