> You can assign 100 students to develop a trojan for a week. At the end of the week, more than 90% of the software are detected as generic trojan by the antivirus.

Probably because 90 of these 100 students have no idea how AV heuristics work and what the trivial tricks are to completely stomp them.

Some of them quickly realize that the AV is flagging all their binaries and they try to evade it. They will soon discover that it is far from trivial.

Don't underestimate the students and don't underestimate the AV. The world is full of surprises.

I had an intern who came to the job with one he had written in his idle time. Nothing detected this, so I am thinking that it is not hard at all.

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