I agree with all the above feedback. This isn't really a new attack it is just a quicker way of getting the pw hash vs having to wait for someone to auth or to force it by sending de-auths. Either way the hash still has to be cracked.
The Hashcat folks found this while researching ways to attack the upcoming WPA3 standard. There isn't much Meraki could do for this since it is an inherent flaw with WPA2. Moral of the story. If possible, use a long password so it cannot easily be cracked via rainbow tables etc.
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO If this was helpful click the Kudo button below If my reply solved your issue, please mark it as a solution.