Personal icloud photos got synced to family members without sharing

Photos, Albums (not shared) and folders from my personal photo library appeared all of a sudden on all devices (iOS) of all my family members.

I share the icloud+ 2TB subsription including purchase and app sharing.

Even HIDDEN photos synced to family member apple IDs!!

At that point the Shared Photo Library option was disabled, I only use Shared Albums. No problem with those.

I enabled Shared Photo Library later on to check the options of this feature.

After meddling with the family and icloud sharing options I m missing 30000 photos :(

Only my albums are left on my family member devices, they are empty. On my personal devices, all albums and photos disappeared. How is this possible? Im using icloud sharing for years without mayor problems.

This is a breach of data security! I mean copying hidden photos to several different IDs without asking, permission etc is a very serious issue.

I always felt save keeping my data on icloud, but now after this, you better know. There is something wrong with the icloud sync, sharing, database and permissions.

Removing 30k photos need the outspoken permission by the user.