COMMAND
kernel (ownership)
SYSTEMS AFFECTED
Win2000
PROBLEM
Frank Heyne found following. There are some "features" of the
implementation of the special group CREATOR OWNER in W2K which
results in unexpected behaviour. Windows 2000 handles CREATOR
OWNER different from all other accounts, and different from
earlier versions of Windows NT. Until Windows NT 4.0 this account
applied to the CREATOR of an object, but in Windows 2000 it
applies to the OWNER (at least mostly). The difference becomes
only clear when you change the owner.
If the permissions of CREATOR OWNER are inherited, changing the
owner of an object does not change the ACE of the old owner. This
was normal behaviour under earlier versions of NT. But when the
permissions of CREATOR OWNER of the parent object were changed
after the owner of the child object was changed, W2K will replace
the ACE for the old owner with one for the new owner. So we have
the problem that sometimes the settings for CREATOR OWNER apply
for the current owner and sometimes they do not.
Because this is a problem which is impossible to explain shortly,
Frank posted here only a summary. An exhaustive discussion of the
problem (on the example of registry keys) is available on
http://www.heysoft.de/nt/reg/w2k/RegDACL_er2.htm#D2
SOLUTION
The design of the security descriptions of objects should be
enhanced: Like the inheritance flags introduced with W2K, a flag
marking the ACEs of owners should be used. This way the operating
system can change the ACL on the fly when the owner is changed.