I know that windows source code is proprietary so how do hackers and others know what are the available exploits in windows so that the viruses can take their advantage.
closed as too broad by tlng05, Tobi Nary, Steffen Ullrich, Matthew, S.L. Barth Aug 2 '17 at 8:44
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- The computer still has to be able to execute a program and therefore you have the machine code available. Figuring out how a program works from there is the most common form of reverse engineering.
- You don't have to exploit windows to write a virus for windows. People run all kinds of programs on windows and it's enough to exploit any one of them.