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How does one read logon and logoff events from the Windows event log, and retrieve the corresponding information for each user from Active Directory, using Powershell?

Autumn Baril
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2 Answers2

6

The following script will read Winlogon events from the System log, retrieve information from AD based on each user's SID, and display the results in a generated HTML page. The results of each AD lookup are cached to prevent unnecessary round-trips to the AD server.

# event id 7001 is Logon, event id 7002 is Logoff
function WinlogonEventIdToString($EventID) {switch($EventID){7001{"Logon";break}7002{"Logoff";break}}}

# look up SID in Active Directory and cache the results in a hashtable
$AdUsers = @{}
function SidToAdUser($sid) {
  $AdUser = $AdUsers[$sid]
  if ($AdUser -eq $null) {
    $AdUser = $AdUsers[$sid] = [adsi]("LDAP://<SID=" + $sid + ">")
  }
  return $AdUser
}

$outputFilename = [System.IO.Path]::GetTempPath() + "DisplayLatestLogonEvents.html"

# the first Select extracts the SID from the event log entry and converts the event id to a descriptive string
# the second Select is responsible for looking up the User object in Active Directory, using the SID
# the final Select picks the various attribute data from the User object, ready for display in the table
# to retrieve only recent log entries, one can use something like this in Get-EventLog: -After (Get-Date).AddDays(-14)
Get-Eventlog -Logname "System" -Source "Microsoft-Windows-Winlogon" -InstanceId 7001,7002 `
  | Select TimeGenerated, @{n='Operation';e={WinlogonEventIdToString $_.EventID}}, @{n='SID';e={$_.ReplacementStrings[1]}} `
  | Select TimeGenerated, Operation, @{n='AdUser';e={(SidToAdUser $_.SID)}} `
  | Select TimeGenerated, Operation, `
           @{n='Username';e={$_.AdUser.sAMAccountName}}, `
           @{n='Full name';e={$_.AdUser.firstname + " " + $_.AdUser.lastname}}, `
           @{n='Title';e={$_.AdUser.title}}, `
           @{n='Department';e={$_.AdUser.department}}, `
           @{n='Company';e={$_.AdUser.company}} `
  | ConvertTo-HTML -Head "<style>td, th { border:1px solid grey }</style>" | Out-File $outputFilename

# this will open the default web browser
Invoke-Expression $outputFilename
Autumn Baril
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0

With Windows 10 professional, a member of Active Directory domain, this script will generate a list of logon / logoff times for the selected user, includes events from screensaver lockscreen. Powershell script to log active work hours, no application needed.

# original source: https://community.spiceworks.com/topic/764481-get-logon-off-workstation-lock-unlock-times 
# cleaned up, filtered by username, and included lock by screensaver timeout by kevin, Dec 2018
# must enable auditing via secpol.msc
# Security Settings -> Advanced Audit Policy -> System Audit -> Logon/Logoff -> Audit Other Logon/Off Events -> On Success

$days = 30
$username = "kevin"

Write-Host "Retrieving last $days days of user: $username, logon/logoff activity... please wait

$events = @()
$events += Get-WinEvent -FilterHashtable @{
    LogName='Security'
    Id=@(4624,4800,4634)
    StartTime=(Get-Date).AddDays(-$days)
}

$type_lu = @{
    4624 = 'Logon'
    4800 = 'Logoff' # screensaver lock
    4634 = 'Logoff' # explicit
}

$ns = @{'ns'='http://schemas.microsoft.com/win/2004/08/events/event'}
$target_xpath = "//ns:Data[@Name='TargetUserName']"
$usersid_xpath = "//ns:Data[@Name='UserSid']"

If($events) {
    $results = ForEach($event in $events) {
        $xml = $event.ToXml()
        Switch -Regex ($event.Id) {
            '4...' {
                $user = (
                    Select-Xml -Content $xml -Namespace $ns -XPath $target_xpath
                ).Node.'#text'
                Break
            }
            '7...' {
                $sid = (
                    Select-Xml -Content $xml -Namespace $ns -XPath $usersid_xpath
                ).Node.'#text'
                $user = (
                    New-Object -TypeName 'System.Security.Principal.SecurityIdentifier' -ArgumentList $sid
                ).Translate([System.Security.Principal.NTAccount]).Value
                Break
            }
        }
        if($username -eq $user) {
            New-Object -TypeName PSObject -Property @{
                Time = $event.TimeCreated
                Id = $event.Id
                Type = $type_lu[$event.Id]
                User = $user
            }
        }
    }

    If($results) {
        $results
    }
}

Example output:

C:\WINDOWS\system32>powershell -file C:\desk\path\timetracker.ps1
Retrieving last 10 days of user: kevin, logon/logoff activity

Time                   User    Id Type
----                   ----    -- ----
12/4/2018 1:39:22 PM   kevin 4634 Logoff
12/4/2018 1:39:19 PM   kevin 4800 Logoff
12/4/2018 1:10:28 PM   kevin 4634 Logoff
12/4/2018 1:10:28 PM   kevin 4624 Logon
12/4/2018 12:57:32 PM  kevin 4634 Logoff
12/4/2018 12:57:32 PM  kevin 4624 Logon
12/4/2018 12:29:43 PM  kevin 4624 Logon
12/4/2018 11:48:11 AM  kevin 4634 Logoff

To debug this script, I opened Event Viewer eventvwr.msc, and used this custom filter (XML).

<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">*[System[(EventID=4624)] and EventData[Data[@Name='TargetUserName']='kevin']]</Select>
  </Query>
</QueryList>

Powershell also has Get-EventLog cmdlet, but I found it lacking in options.

Kevin
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