This article will review the basics in general security and explain how to apply it to two Linux distributions–Ubuntu and Kubuntu.
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A program is only secure if it has no vulnerabilities. Even the most popular software can have a hidden one. When someone fixes the vulnerability,a new version of the program is usually released. Both Ubuntu and Kubuntu have software repositories dedicated to security updates.When a vulnerability is fixed, a package of the program is released so that you can download it. Ubuntu and Kubuntu usually enable some of their security update repositories by default, but it is always a good idea to check to see if all of them are enabled. You may also want to specify how often you want your computer to look for security updates–and even install them–while you're at it (for Ubuntu 6.06only).