Virus writers use open-source methods | CNET News.com
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Malicious software writers are increasingly using open-source methodologies when developing their code, according to security company McAfee.

In its Global Threat Report for 2006, McAfee warned that more hackers are sharing source code and ideas freely. This includes distributing source code with documented explanations and annotations of how that code works, which helps programmers adapt it.

McAfee said that this can be an extremely effective way of developing code, both legitimate and malicious.