Apple has released Security Update 2010-003 (Leopard-Client) to address a critical vulnerability in the way Apple Type Services in Mac OS X 10.6 Snow Leopard parses embedded fonts. Users who view or download any documents containing maliciously crafted embedded fonts run a risk of arbitrary code execution. The update addresses this issue by improving index checking. This vulnerability was first demonstrated by Charlie Miller at the Pwn2Own conference 20 days ago, which shows a reasonably quick response on Apple's part. A nearly identical update - Security Update 2010-003 (Leopard-Server) - that eliminates the same vulnerability is available for Leopard Server. The update requires you are running Mac OS X 10.5.8 and is available via Software Update and the Apple Support Downloads page. (Free, 218.6/379.5 MB)
Sleep (and Lock) Your Screen
When you are walking away from your computer, it's fairly common practice to start your screen saver and lock your screen. But did you know that there is a built-in keyboard shortcut in Mac OS X to sleep the screen?
Press Control-Shift-Eject and your monitor sleeps without engaging the screen saver.