How can I prevent a security breach?

Question

Can anyone tell me if there is a way to prevent a hacker from gaining access to my computer. A Kevin Mitnick wannabe was successful in breaking into my computer while I was away from it by using some kind of hacking program.

Answer 1

What was the hacking program? How did this person gain access?
If anyone has physical access to your Mac (not just across a network) then only an encryption application can protect your data. Nothing can prevent your computer from being erased or your applications from being used.
The only way you prevent your Mac from being hacked is to make sure that it is not physically accessible to the hacker. You can have all the wires accessible but you must prevent your computer from being opened.
Now, that doesn't mean someone with some smarts can't break into your Mac using a network sniffer while you choose to use a weak password or no password at all. No one thing can stop a hacker but you must rely on layers of security:
1. Use a strong password <http://www.apple.com/macosx/tips/password13.html> and do not set your computer to automatically log in to any account.
2. Turn off services you don't use <http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh1921.html>.
3. Turn on FileVault <http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh1906.html>.
4. Password protect and encrypt your wireless network <http://docs.info.apple.com/article.html?path=Airport/5.0/en/ap2084.html>.
5. To prevent someone from putting your computer into Target Disk mode or booting your Mac from anything other than the internal hard drive you can set an Open Firmware password <http://docs.info.apple.com/article.html?artnum=106482>. This can be circumvented if someone can access the inside of your Mac.
6. If you use applcations such as Microsoft Office take advantage of their password capabilities. These can be cracked but add an additional layer of security.
7. Use an application such as Stuffit to compress, encrypt and password protect very sensitive documents.
8. Store your backup tapes or disks in a fireproof safe or a safety deposit box. Securing your Mac is useless if hackers can get to your backups.
I'm sure other security measures are available as well. Those that I mention above protect different vulnerabilities but collectively they make your Mac more secure.
Hope this helps!
bill