An organization provides information to its supply chain partners and customers through an extranet infrastructure. Which of the following should be the GREATEST concern to an IS auditor reviewing the firewall security architecture?
A.
A Secure Sockets Layer (SSL) has been implemented for user authentication and remote administration of the firewall.
B.
Firewall policies are updated on the basis of changing requirements.
C.
inbound traffic is blocked unless the traffic type and connections have been specifically permitted.
D.
The firewall is placed on top of the commercial operating system with all installation options.
Explanation:
The greatest concern when implementing firewalls on top of commercial operating systems is the potential presence of vulnerabilities that could undermine the security posture of the firewall platform itself. In most circumstances, when commercial firewalls are breached that breach is facilitated by vulnerabilities in the underlying operating system. Keeping all installation options available on the system further increases the risks of vulnerabilities and exploits. Using SSL for firewall administration (choice A) is important, because changes in user and supply chain partners’ roles and profiles will be dynamic. Therefore, it is appropriate to maintain the firewall policies daily (choice B), and prudent to block all inbound traffic unless permitted (choice C).