In response to your question edit where you have switched from WEP to WPA but now get the error message, "No valid WPA handshakes found.", I repeat my earlier advice. I would suggest you go and read how to use the tool, for example on the aircrack website.
The new side-channel leak is located in the password encoding algorithm of Dragonfly.This algorithm first tries to find a hash output that is smaller than the prime of the elliptic curve being used.With the default NIST curves, such a hash output is practically always found immediately.However, with Brainpool curves, several iterations may have to be executed before finding a hash output smaller than the prime.The number of iterations that didn't have such a valid hash output depends on the password being used and on the MAC address of the client.Simplified, the resulting timing and execution differences can be measured by an adversary.For example, in Figure 1 below,we can see that for the blue and orange MAC addresses (i.e. clients) the desired hash output was, on average, found in different iterations. d2c66b5586