user account "effective permissions" with powershell

Question

I need to compare AD users permissions (one user can "unset" an attribute and another cannot, both can change it).

How can I dump/compare user account "effective permissions" which I find when I go to user account > Security > Advanced > Effective Permissions (and select an user account) with powershell?

Answer 1

We were in a similar situation once and needed to know who all could delete one of our main OUs, so we figured that maybe we should dump the ACL on the OU and look for everyone who had delete permissions on the object. Of course dsacls was very helpful in this regard and we could dump the ACL on it easily.

But then, as we started looking at the ACL, we found that it had almost 60 permission entries, including about half a dozen deny entries, some of which were direct and others inherited. We initially didn't consider the denies and came up with a list of about 200 users who could delete the OU, but that did not seem right (; it seemed too high.) Then, we realized that we had to intersect the denies with the allows!

So we flattened all deny permissions, and all allow permissions, but then we had to figure out which of these denies would apply, since some of them were inherited, and I believe the inherited ones don't negate any direct allows, so that took some more pain-staking work, and while doing it we realized that some of those inherited permissions did not apply to the object, so we had to start from scratch!

Finally, we almost gave up, and when I asked one of our Enterprise Admins, he said what we needed to do was determine Effective Permissions on our OU, and he pointed us to the Effective Permissions Tab in the Active Directory Users and Computers snap-in.

So we launched ADUC and navigated to the Effective Permissions Tab, and figured it would be a matter of clicking OK somewhere. However, we soon realized that it needed us to enter each person's name individually. Now, we have almost 2000 people in our environment, so there was no way we could put in 2000 people's names one by one. The other thing was that even for a single person, it would show us all the effective permissions for that person, and in technical terms, which we would have to further refine.

We then figured we'd give Powershell a shot, and looked at many options to do this using Powerhsell, but there was no easy to determine effective permissions in AD using Powershell, which was disappointing. In particular, we tried Quest's free PowerShell commands Get-QadPermission useraccountname and Get-QADUser -Name useraccountname, but we were disappointed to see that this only retrieved the list of all permissions specified for a given user. It did not reveal the Effective Permissions granted to a user. We found ourselves having to start with the results it brought back to then manually try and determine effective permissions, which was not worth our time.

So, we had almost given up hope, but before quitting we thought we would just Google "Active Directory Effective Permissions Tool" with the hope that there must be something out there that could do this for us. I am glad we did because we found a tool that could do exactly what we needed: figure out effective permissions on our OU and give us the ability to export these effective permissions -

http://www.paramountdefenses.com/goldfinger_capabilities_true_effective_permissions_for_active_directory.html

We found that this tool (called Gold Finger for AD) has the ability to determine Effective Permissions on Active Directory objects, and provide the output such that we could easily see the list of all users who had "effective permissions" for a specific right on an object. For instance, we were able to use it to determine and enumerate the list of all admins who had "effective delete access" rights on the OU we were interested in.

It has turned out to be quite helpful for us, and maybe it could be of help to you too. I just thought I would share this because I've been the dsacls route and I wouldn't want you to go through the same pain we did in trying to manually do this. Its just too painful to do do manually.

Answer 2

Using Quest Free PowerShell Commands for Active Directory is simple:

Get-QadPermission useraccountname -Inherited 

or better way:

Get-QADUser -Name useraccountname -SecurityMask DACL | Get-QADPermission -Inherited -SchemaDefault

This return all effective permission Inherited or Explicit assigned for the user 'useraccountname'

The comparison can be made with compare-object. A very simple example:

compare-object (Get-QADPermission userA -Inherited | select Rights) (Get-QADPermission userB -Inherited | select rights)