How viruses can infect .exe, .dll, .com files if they have something like this:

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Closed due to the fact that the issue is too common for the participants D-side , Denis , Vladimir Martyanov , pavel , Kromster 7 Oct '16 at 19:34 .

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  • 9
    And what does it bother? - D-side
  • one
    The topic is large and very extensive. And what you see is the result of using the wrong viewer. The same IDA will show much more useful information. - Vladimir Martyanov
  • 2
    The structure of the exe files is perfectly described, each "character" in them is decodable, for these are processor instructions. Study the assembler and then much will become clear - Mike

1 answer 1

In executable files are sets of instructions, which are defined byte sequences. Accordingly, the replacement of one set of instructions with another leads to the fact that the program begins to perform not what was planned.