In order for an attacker to exploit these vulnerabilities, he or she would have to convince an iCal user to open an .ics file sent via e-mail or hosted on a Web server.
Source
This is a discussion on Apple's iCal Vulnerable To Hackers within the Member Discussion forums, part of the Community Center category; In order for an attacker to exploit these vulnerabilities, he or she would have to convince an iCal user to ...
In order for an attacker to exploit these vulnerabilities, he or she would have to convince an iCal user to open an .ics file sent via e-mail or hosted on a Web server.
Source