Permissions of /Users keep changing back to drwxrwxrwx

I use the Disk Utility to repair it. But the permissions change back after reboot.

Permissions differ on “private/etc/aliases”; should be lrwxr-xr-x ; they are -rwxr-xr-x . Permissions differ on “Users”; should be drwxr-xr-x ; they are drwxrwxrwx . Permissions differ on “Users/Shared”; should be drwxrwxrwt ; they are drwxrwxrwx .

System: Mac OS X 10.9.3

This problem was caused by a bug introduced by an Apple software update. iTunes 11.2.1 has been released to fix the issue.

iTunes 11.2.1

Impact: A local user can compromise other local user accounts

Description: Upon each reboot, the permissions for the /Users and /Users/Shared directories would be set to world-writable, allowing modification of these directories. This issue was addressed with improved permission handling.

This vulnerability was assigned the security identifier CVE-2014-1347.

This is a problem where iCloud's Find My Mac interacts poorly with an iTunes update. (Specifically iTunes 11.2)

The fix and cause are documented expertly on Rich Trouton's blog:

• http://derflounder.wordpress.com/2014/05/16/users-folder-being-hidden-with-itunes-11-2-installed-and-find-my-mac-enabled/

The fix is to disable find my Mac and then run a script to repair the permissions and visibility of the potentially affected folders. This will likely be fixed rapidly by Apple since it can cause some serious issues and confusion when the /Users folders are incorrectly secured.

I've exactly the same problem after updating to 10.9.3 yesterday but with slightly different folders...

Users folder same problem as with yours

Users/Shared same problem as with yours

and

Applications/Safari.app/Contents/Resources/Safari.help/Contents/Resources/index.html

should be: Irwxr-xr-x

is: -rwxr-xr-x

Doesn't matter what I'll try, after the next reboot the problem say's hello again.

Well I've not the chance to test it yet but you might wanna give the following a try:

Start your computer with Alt + CMD + P + R in order to a PRAM reset. Start your computer with CMD + R for recovery partition boot Launch Disc Utility and repair the permissions. Quit Disk Utility and open the Terminal (Utilities -->> Terminal) and type:

cd /Volumes/Macintosh\ HD (or the name of your partition) 
chmod 755 Users 
chmod 755 Users/Shared 
chflags nohidden Users 
chflags nohidden Users/Shared

Restart, normally everything should be back to normal