This is officially from Apple and is there, among other things, to synchronize photos and videos taken with the iPhone via the Apple cloud with Windows.
Affected users have various iPhone Pro models in use and get videos via the Apple software on Windows. After the explicit download under Windows 10 or 11, however, the clips are said to break, and when they try to play them, they supposedly only show a black screen.
So far so unspectacular – a bug that can occur every day between cloud offers and users. But it goes even further: According to the users, third-party photos are sometimes displayed that are supposed to show football games or family celebrations with unknown people. It is speculated here that the Pictures from other iCloud users could come from and somehow end up in the wrong photo area.