Update: on November 4 FlutterFlow released v7.2.33+ with the security fixes for the Firebase certificates.
For the iOS side cloud_firestore went to 6.10.2 in my export. According to the Firebase page 6.10.1 and 6.10.2 are excluded from the affected versions. I've just made a new export and the other Firebase packages were updated too: firebase_core 4.15.2, firebase_auth 6.7.1, cloud_functions 6.5.1, firebase_messaging 16.7.1, firebase_storage 13.6.1, firebase_app_check 0.4.9, firebase_performance 0.11.7. Now we can recompile and republish, but the problem remains of getting those who have the old version to install the new one.