You can detect SonicWall Email Security appliances using this tool.
SonicWall Email Security is ideal for organizations that need a dedicated on-premises solution. SonicWall’s solution can be deployed as a hardened physical appliance, robust virtual appliance or software application. The multi-layered solution provides comprehensive inbound and outbound protection, and defends against advanced email-borne threats such as ransomware, zero-day threats, spear phishing and business email compromise (BEC).
If attackers detect the technology used, they will try to detect vulnerabilities related to this application.
Only use components that do not have known vulnerabilities, only use components that when combined to not introduce a security vulnerability, and ensure that a misconfiguration does not cause any vulnerabilities.