Media reports are currently reporting a new potential attack on the WPA2 security protocol, which involves attackers taking advantage of a weakness in the "Pairwise Master Key Identifiers" function. This attack uses brute-force cracking, a trial and error method that attempts to decode encrypted data such as passwords. This is not a new type of attack and involves an exhaustive amount of time and effort.
AVM doesn't see any practical implications if you choose a WPA2 key that is sufficiently strong and complex. As a general rule, you should only use network keys that are recognized as "good" or "strong". Thanks to its length, the FRITZ!Box network key that is individually preset upon delivery is complex enough.