The goTenna Pro series uses a weak password for the QR broadcast message. If the QR broadcast message is captured over RF it is possible to decrypt it and use it to decrypt all future and past messages sent via encrypted broadcast.
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.