Cupertino (CA) - Apple released its fifth security update of 2007, patching potential problems in iChat, CoreGraphics, and other system commands.

As part of the update, it fixes an issue in iChat that could allow people to send malicious code and remotely cause the application to close. The exact same problem is fixed in CoreGraphics.

Also patched is a vulnerability that would allow local users to take over system priveleges and overwrite system files. Most of the other updates relate to internal commands, and prevent malicious code from attacking the computer.

Mac users can get the update by using the built-in update service or from Apple's website.