Security-Corporation ID : SC-0783
URL : http://www.security-corporation.com/articles-20031124-001.html
Author : Santino Rizzo
Product : Mac OS X 10.3
Source Message Contents :
Vendor: Apple Computer
Target: Finder authentication in Mac OS X 10.3
If a user in the admin group tries to write to the /System/Library directory, which has owner permissions of root:wheel and file permissions of 755, they are presented with an authentication dialog from the Finder. Upon authenticating as an admin they are given full access to the directory, circumventing the root permissions. This occurs even if the admin group is removed from the sudoers list.

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