The flawed iTunes 11.2 update that users downloaded along with OS X 10.9.3 last week was addressed by Apple about a day later.

Those quick to update their Apple machines running OS X Mavericks almost immediately began reporting that their /Users and /Users/Shared folders were no longer visible, according to an Apple post, which adds this could happen if Find My Mac is enabled in iCloud System Preferences.

The release of iTunes 11.2.1 about 24 hours later addressed that, and other security issues.

According to a follow-up post by Apple, a local user was able to compromise other local user accounts because, upon rebooting the system, the /Users and /Users/Shared directories are set to world-writable – ultimately enabling modifications to the directories.

Improved permission handling fixed the issue, according to the post.