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A zero day attack, also known as a zero hour attack, takes advantage of computer vulnerabilities that do not currently have a solution. Typically, a software company will discover a bug or problem with a piece of software after it has been released and will offer a patch — another piece of software meant to fix the original issue. A zero day attack will take advantage of that problem before a patch has been created. It is named zero day because it occurs before the first day the vulnerability is known.
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