Is a virus scanner required for each host if a network has a firewall and the email is scanned for malware?

A virus scanner is indeed required for each host even if a network has a firewall and email is scanned for malware because these measures alone do not provide comprehensive protection against all malware threats. While firewalls are essential for controlling incoming and outgoing network traffic based on predetermined security rules, they primarily protect against unauthorized access and certain types of attacks from external sources.

Email scanning is beneficial for filtering out malicious attachments or links contained within emails, but it does not address other potential entry points for malware, such as removable media (like USB drives), internal network threats, or users inadvertently downloading malware from legitimate websites.

By having a virus scanner on each host, organizations can actively monitor and mitigate threats that may bypass the firewall and email filters. This is crucial for detecting and removing malware that may enter via other vectors, ensuring the integrity and security of the entire network.