When you share the calendar some private events are leaked

[section1]

Steps to reproduce

1. User B shares the calendar with user c
2. User A creates recursively an Event with user B as attendant and choose "When share show only busy"
3. User C see that User B has an event an displays as "Busy" ( pic # 1 ). works fine
4. User A change the time of a simple event of this recursively "Secret Event"
5. User C see the full event in the shared calendar

Expected behavior

User C always should see the events as "Busy" for the user B shared calendar

Actual behaviour

User C see the modified event with full details
The same happens with the public link you can see the modified event with full details ( pic # 2 )

User A calendar:

Day 11 have the modified instance of the event. Public link:

Calendar app version

4.5.2

CalDAV-clients used

No response

Browser

firefox 118

Client operating system

linux ubuntu

Server operating system

linux ubuntu

Web server

Apache

Database engine version

MariaDB

PHP engine version

PHP 7.4

Nextcloud version

25.0.13

Updated from an older installed version or fresh install

Updated from an older version

List of activated apps

Enabled:
  - calendar: 4.5.2
  - circles: 25.0.0
  - cloud_federation_api: 1.8.0
  - contactsinteraction: 1.6.0
  - dav: 1.24.0
  - federatedfilesharing: 1.15.0
  - federation: 1.15.0
  - files: 1.20.1
  - files_rightclick: 1.4.0
  - files_trashbin: 1.15.0
  - files_versions: 1.18.0
  - logreader: 2.10.0
  - lookup_server_connector: 1.13.0
  - notifications: 2.13.1
  - oauth2: 1.13.1
  - password_policy: 1.15.0
  - privacy: 1.9.0
  - provisioning_api: 1.15.0
  - related_resources: 1.0.4
  - serverinfo: 1.15.0
  - settings: 1.7.0
  - systemtags: 1.15.0
  - theming: 2.0.1
  - twofactor_backupcodes: 1.14.0
  - updatenotification: 1.15.0
  - user_ldap: 1.15.0
  - user_status: 1.5.0
  - viewer: 1.9.0
  - workflowengine: 2.7.0

Nextcloud configuration

No response

Web server error log

No response

Log file

No response

Browser log

No response

Additional info

No response

[section1]

Fixed in: nextcloud/server#45309