Ubuntu is billed as ultra-secure, but its default install has flaws. Here are the mods you need to make to protect your system.
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An often overlooked yet highly vulnerable area of computing is protection for machines while they're booting up. While simply keeping unauthorized users from having access to your computer is the best policy, sometimes that isn't possible. Thus this guide, over at the UbuntuForums, gives detailed instructions for protecting your computer while it's booting up.