True or False: Network firewalls can fully protect hosts from zero-day exploits.

Network firewalls are essential components of network security, but they cannot fully protect hosts from zero-day exploits. Zero-day exploits take advantage of vulnerabilities that are not yet known to the software vendor or the public, which means there are no patches available to mitigate these vulnerabilities at the time of the attack.

While firewalls can help prevent certain types of traffic, they operate based on known patterns, signatures, and rules. Since zero-day vulnerabilities are unknown, a firewall's capabilities to filter or block specific vulnerabilities are limited. Therefore, relying solely on a network firewall for protection against such exploits is insufficient. In addition to firewalls, a multi-layered security approach that includes endpoint protection, regular software updates, threat intelligence, and user education is necessary to safeguard against zero-day threats.

This context highlights the importance of understanding that while firewalls are critical for network defense, they do not provide comprehensive protection against all types of cyber threats, particularly those that exploit newly discovered vulnerabilities.