Skip to main content

Finding Old or Unused Accounts with Powershell

Recently I tried to find accounts that haven't been used in a long time. In order to do this I wrote a powershell script to get the last logon time for all accounts in the domain. The problem is, each domain controller contains a different time for the Last Logon depending on which was used as the logon server. In order to get an accurate time we need to get the last logon from each domain controller for each user. This is NOT a fast process. If there are 500 users and 4 domain controllers that is 2000 requests. On top of that some of the domain controllers might be a different location with a slower WAN link which will make it go even slower.

Note: This script requires Quest Software's Active Directory cmdlets. You can download it from here:

Add-PSSnapIn Quest.ActiveRoles.ADManagement -ErrorAction SilentlyContinue

$dcs = Get-QADComputer -ComputerRole DomainController
$users = Get-QADUser -SizeLimit 0

#$ErrorActionPreference = "Continue"

foreach ($user in $users) {
    #"Searching $($user.Name)"
    $lastlogon = $null
    foreach ($dc in $dcs) { 
        $dclogon = (Get-QADUser -Service $dc.Name -SamAccountName $user.Name).LastLogon
        #"$($user.Name) $($dc.Name) $dclogon"
        if ($dclogon -ne $Null) {
            if ($lastlogon -lt $dclogon) {
                #write-host "replacing"
                $lastlogon = $dclogon
    if ($lastlogon -eq $Null) { $lastlogon = [dbnull]::value }
    #"$($user.Name) $lastlogon"
    $o = New-Object PSObject
    $o | Add-Member NoteProperty "User" $user.Name
    $o | Add-Member NoteProperty "LastLogin" $lastlogon
    $o | Add-Member NoteProperty "DisplayName" $user.DisplayName
    $o | Add-Member NoteProperty "Disabled" ([ADSI]("LDAP://$($user.DN.ToString())")).PsBase.InvokeGet("AccountDisabled")
    $o | Add-Member NoteProperty "DistinguishedName" $user.DN
    $o | Add-Member NoteProperty "Title" $user.title
    $o | Add-Member NoteProperty "SamAccountName" $user.SamAccountName
    $o | Add-Member NoteProperty "LastName" $user.LastName
    $o | Add-Member NoteProperty "FirstName" $user.FirstName
    Write-Output $o

Assuming you put this script in the file Get-LastLogin.ps1 you can find all accounts that haven't logged in during the past 90 days.
.\Get-LastLogin.ps1 | where {$_.LastLogin -lt (Get-Date).AddDays(-90)}

If you want to sort the results and save it as a csv you can do this:
.\Get-LastLogin.ps1 | where {$_.LastLogin -lt (Get-Date).AddDays(-90)} | | Sort-Object @{expression="LastLogin";Descending=$true},@{expression="User";Ascending=$true} | Export-Csv "c:\lastloginreport.csv" -noTypeInformation


Popular posts from this blog

Extracting Users from LinkedIn via Burp

We do a lot of pen tests and red teaming at Red Siege. Part of reconnaissance includes gathering a list of employees from a target organization. Typically, those usernames will be used in either phishing or password spray attacks (trying a few passwords across a long list of users). LinkedIn is a treasure trove of information! I'm going to use my good friends at Black Hills Information Security as my guinea pigs (sorry, and thanks!). The tool is here. First, let's look at what the data from LinkedIn looks like a response.

After performing a search for "Black Hills Information Security" we can look at the requests and responses. LinkedIn includes all the user information in responses to "/voyager/api/mux".

We can click the "Next" button a few times in our search to load multiple pages of info. Now, for the extraction. First, select everything in the "HTTP history" with Ctrl+A or Command+A on macOS. Second, right click in the top portion. …

Beyond Net User - Part 1: Limitations of the "Net" commands

I've had a number of cases where the Windows "net user", "net group", and "net localgroup" have failed me. I've had SQLMap fail to give the last line of "net user" output, I've had "net group /domain" not give me the full names (I still don't get how that failed!). On top of that, the commands don't support wildcards. Also, the output of those commands is a pain to parse due to the columns. I'd much prefer to use the AD PowerShell cmdlets, but those aren't always available. I set to find other ways to get the same data. First, let's look at the limitations of the "net" commands.
Net command limitations Hiding Groups in Groups Often when pen testing and red teaming, we would like to figure out information about the domain, most notably the members of the Domain Admins group. Output of the net group "domain admins" command as shown below.

It shows three members: Administrator, sqlagent,…

Beyond Net User - Part 2: DS Commands

In the previous post we discussed some of the limitations of Net commands. Most notably, the output limitation (doesn't show all groups) and it doesn't allow for flexible searching. In this post we'll discuss the DS commands to get around these limitations.
DSGet, DSQuery, DS* While these tools are useful, they aren't always available. As a pen tester and red teamer, I have to live with what I can find on the systems I come across. I find that these tools are still more widespread than the latest PowerShell Active Directory cmdlets, at least on non-system administrator systems. Here is a useful Stack Overflow post on the subject. Recursive Searches In the last post, we discussed a limitation in net group in that it doesn't show groups in other groups. The DS commands do! As a reminder, let's take a look at what we saw with net group when looking at the list of domain administrators.

Now let's do the same search, but use the dsquery and dsget.
dsquery group -…