latest operating system, Leopard, comes with a useless firewall. According to a report from Heise Security, the firewall failed every test.
Heise points out that by default, Leopard's firewall configuration is set to 'allow all incoming connections.' If you had a firewall activated before you upgraded you will find it switched off when you install Leopard.
The firewall can't distinguish between trusted networks, such as a protected company network, and dangerous wireless networks in airports or even direct Internet connections. The firewall sees attacks and ignores them.
Despite claiming that it is a safe haven from hackers who often have a field day with Microsoft machines, Hiese said that Apple is in the same position regarding security issues that Microsoft faced four years ago.