We don’t recommend using a software firewall compared to a hardware solution. Hardware Firewalls are more secure and are not likely to be bypassed by hackers or a like. In recent news, it has been reported by BetaNews through its own testing this morning that a critical patch, released yesterday by Microsoft as part of a worldwide DNS bug fix effort, can and does impact the functionality of software firewalls.

Multiple reports from users since yesterday afternoon have complained of systems incapable of contacting the Internet after having implemented patch KB951748. This patch makes a major change to the way the operating system handles DNS requests. Specifically, it implements a system that enables source port randomization — a way to scramble the address from which a request is placed — as a security measure to thwart malicious users from being able to craft false DNS responses, and thus “poison” the caches of DNS servers.

It is a very serious fix to what could have been a catastrophic exploit, and it’s being implemented not just on Windows but on Linux, and within routers and other network equipment as well.

This flaw affects ZoneAlarm and other Firewall software applications.