The thing is, the hack could be detected right now, that's the beauty of VAC.
This is how the VAC bans works:
1. Hack gets detected
2. After a period of time a wave of people who used the hack get banned at a single time (Not everyone will get banned at once)
3. The hack users who did not get banned in the wave start to get banned at random times (Like a week after the wave, or a month, or maybe longer)
My point being, no one knows when the hack is detected, meaning it could be detected when you used it.
Lets say it wasn't detected at the time of when you used it, then no, you will not get VAC banned in a month or so, but like I said, no one can know exactly when a hack gets detected.