The goTenna Pro App uses a weak password for sharing encryption keys via the key broadcast method. If the broadcasted encryption key is captured over RF, and password is cracked via brute force attack, it is possible to decrypt it and use it to decrypt all future and past messages sent via encrypted broadcast with that particular key. This only applies when the key is broadcasted over RF. This is an optional feature, so it is recommended to use local QR encryption key sharing for additional security on this and previous versions.