Would it be immoral to murder a malware author?

I submit that no, it would not be immoral to murder a malware author. If somehow convicted of the act conclusively that they did write and distribute malware, that person should be marked as fair game. Why? Because it is in our best rational self interest. It would be moral. Anyone who had spent hours or days trying to recover a computer from their product of malicious mischief would be morally in their rights to murder them. That is what I think right now after spending hours trying to (for at least the third time) recover a computer from a malware infestation.