What if NRF24L01 is connected to 5v?

The title suggests it all

It was an accident for the record...

What's the worst that can happen?

A bit of smoke, perhaps?

jremington: A bit of smoke, perhaps?

Really? Not in my case

I tested them and they didn't receive from a working Tx. I think it's a wiring issue, but then I noticed that it was connected to 5v

The NRF24L01 tolerates 5V signals on its I/O pins, but powering it by 5V kills it sooner or later, mostly sooner.

I have abused mine accidentally from time to time without an immediate failure - even connected + and - backways. However I would not recommend using more than the recommended 3.6v max.