PI Services

Le blog des collaborateurs de PI Services

Intune : Trouver le dernier utilisateur connecté à un ordinateur en utilisant Microsoft Graph explorer

Dans la console d'administration Intune, Microsoft n'a pas ajouté un rapport ou une propriété ordinateur pour identifier le dernier utilisateur connecté à un device (last logged on user).

Si vous souhaiter identifier quel est le dernier utilisateur connecté à un ordinateur, vous pouvez utiliser l'interface graphique Microsoft Graph explorer: https://developer.microsoft.com/en-us/graph/graph-explorer

Dans Microsoft Graph explorer, précisez dans le Request body, l'url de l'ordinateur recherché: https://graph.microsoft.com/beta/deviceManagement/managedDevices/{<Device ID>}  (remplacez <Device ID> par la vraie valeur qui peut être récupérée depuis Azure AD dans les propriétés d'un ordinateur).

Nous avons récupéré le "Device ID" de l'ordinateur concerné depuis Azure AD et l'avons remplacé dans l'url comme le montre la capture d'écran ci-dessous, puis nous avons cliqué sur le bouton Run query :

Dans la même capture d'écran, nous pouvons voir dans la partie Response preview (Résultat), l'ID du dernier utilisateur connecté à l'ordinateur.

Avec cet ID, nous pouvons chercher l'utilisateur dans Azure AD.

Script - Crowdstrike - Exemple d'utilisation du module PSFalcon

Falcon Crowdsrike est l'un des antivirus next generation (EDR) les plus en vue et les plus performants du marché.  Le script ci-dessous propose un exemple de requetage de l'API de Crowdstrike via l'utilisation du module Powershell PSFalcon (https://www.powershellgallery.com/packages/PSFalcon)

L'acces et l'utilisation de l'Api Crowdstrike requiert bien sur un abonnement Crowdstrike (https://www.crowdstrike.com/)

Le script utilisant pour l'acces a l'API, une clé d'encryptage (AES.key), un fichier contenant le SecID (SecID.txt), et un fichier contenant la passphrase (pass.txt), il est necessaire de recreer ces éléments avec le contexte de l'abonnement auquel on se connecte (SecID).

Le script interroge l'API pour recuperer des éléments tel que les hotes, les comportements (Behaviors), les detections, les incidents.

 

QueryCrowdstrike.ps1 (11,62 kb)

 

##############################################
### QUERY CROWDSTRIKE WITH PSFALCON MODULE ###
##############################################


<# 

    .SYNOPSIS 
        INTERROGATION D'UN TENANT FALCON CROWDSTRIKE VIA L'UTILISATION DU MODULE POWERSHELL PSFALCON
        NB: LES DONNEES SONT EXTRAITES SOUS FORME D'UN FICHIERS CSV 

    .PARAMETER  
        ClientID : Client ID crowdstrike
        Pass : Password du compte d'acces a l'API
        
        ExportFolder : Dossier d'export du fichier CSV
        LogFolder : Chemin du dossier où creer le log du script

 
    .EXAMPLE 
     .\QueryCrowdstrike.ps1 -CloudUrl "https://api.eu-1.crowdstrike.com"  -ClientID <clientid> -Pass <pass> -ExportFolder ./ -LogFolder ./
#>


[CmdletBinding()]
param(
[Parameter(Mandatory,HelpMessage="Cloud URL")]
$CloudUrl,

[Parameter(HelpMessage="Client ID crowdstrike")]
$ClientID,

[Parameter(HelpMessage="Password du compte d'acces a l'API")]
$Pass,

[Parameter(Mandatory,HelpMessage="Dossier d'export du fichier CSV")]
[string]$ExportFolder="./CSV",

[Parameter(Mandatory,HelpMessage="Chemin du dossier où creer le log du script")] 
[string]$LogFolder="./",

[Parameter(Mandatory,HelpMessage="Chemin de la clé utilisée pour l'encryption du CID et de la passphrase")] 
$KeyFile = "D:\MyFolder\CROWDSTRIKE\AES.key",

[Parameter(Mandatory,HelpMessage="Chemin du fichier contenant le SecID du client")] 
$SecIDFile = "D:\MyFolder\CROWDSTRIKE\SecID.txt",

[Parameter(Mandatory,HelpMessage="Chemin du fichier contenant la passphrase")] 
$PassFile = "D:\MyFolder\CROWDSTRIKE\Pass.txt"


)


# TO RENEW KEY FILE USED FOR CLIENT ID AND PASSPHRASE ENCRYPTION
<#
    # Generate Key File
    $Key = New-Object Byte[] 16   # You can use 16, 24, or 32 for AES
    [Security.Cryptography.RNGCryptoServiceProvider]::Create().GetBytes($Key)
    $Key | out-file $KeyFile

#>


# TO RENEW SECID ENCRYPTION, EXECUTE THE CODE BETWEEN <# #>

<#
    # Create secure string object
    $SecIDFile = "D:\MyFolder\CROWDSTRIKE\SecID.txt"
    $Key = Get-Content $KeyFile
    $SecID = read-host  -Prompt "Enter client SecID" -AsSecureString
    $SecID | ConvertFrom-SecureString -key $Key | Out-File $SecIDFile

#>


# TO RENEW PASSPHRASE ENCRYPTION, EXECUTE THE CODE BETWEEN <# #>

<#
    # Create secure string object
    $PassFile = "D:\MyFolder\CROWDSTRIKE\Pass.txt"
    $Key = Get-Content $KeyFile
    $Pass = read-host  -Prompt "Enter client PassPhrase" -AsSecureString
    $Pass | ConvertFrom-SecureString -key $Key | Out-File $PassFile

#>






# OTHER VARIABLES
# Script Name
$ScriptName = "QueryCrowdstrike.ps1"
# LogName = ScriptName without extension
$Log = $ScriptName.Split('.')[0]


# FUNCTIONS


function Write-Log 
{ 
    <# 
    .SYNOPSIS 
        This function creates or appends a line to a log file. 
 
    .PARAMETER  Message 
        The message parameter is the log message you'd like to record to the log file. 
 
    .EXAMPLE 
        PS C:\> Write-Log -Message 'Value1' 
        This example shows how to call the Write-Log function with named parameters. 
    #> 
    [CmdletBinding()] 
    param ( 
        [Parameter(Mandatory)] 
        [string]$Message,
        [Parameter(Mandatory)] 
        [string]$LogPath, 
        [Parameter(Mandatory)] 
        [string]$LogName
        
    ) 
     
    try 
    { 
        $DateTime = Get-Date -Format ‘MM-dd-yy HH:mm:ss’ 
        Add-Content -Value "$DateTime - $Message" -Path "$LogPath\$LogName.log" 
    } 
    catch 
    { 
        Write-Error $_.Exception.Message 
    } 
} 



            




# Requis si l'import du module echoue en en renvoyant plusieurs messages 'Unable to find [System.Net.Http.(...)*]' 
Add-Type -AssemblyName System.Net.Http 

# Import Module
Import-Module -Name D:\MyFolder\CROWDSTRIKE\Powershell_Module\psfalcon-master\PSFalcon.psm1



$Key = Get-Content $KeyFile

# Get file content and Decrypt ClientID
$ClientID = Get-Content $SecIDFile | ConvertTo-SecureString -Key $key
$ClientID = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto([System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($ClientID))

# Get file content and Decrypt Pass
$Pass = Get-Content $PassFile | ConvertTo-SecureString -Key $key
$Pass = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto([System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($Pass))







# Query for Falcon Token
try
    {
    Request-FalconToken -ClientId $ClientID -ClientSecret $Pass -Hostname $CloudUrl
    }
catch
    {
    $Message = "Error during Request-FalconToken - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }


# Test if Test-FalconToken return True
if ($(Test-FalconToken).token -eq $true)  
      {
      $Message = "Token is valid - OK"
      write-host -F Green $Message
      Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
      }
Else
    {
    $Message = "Problem with Token - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }




# GET DATA

#region Falcon Hosts 

# Get Falcon Hosts (exemple option -filter:  –Filter "hostname:'SRV'")
try
    {
    $FalconHosts = Get-FalconHost -All -Detailed
    #$FalconHosts | select hostname,os_version,agent_version,status | ft -AutoSize
    }
catch
    {
    $Message = "Problem during Get-FalconHost - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }


# Convert To CSV
 try
    {
    $FalconHostsCSV = $($FalconHosts | select `
        hostname,
        os_version,
        platform_name,
        status,
        agent_version,
        config_id_base,
        config_id_build,
        @{Name='First_Seen';Expression={[datetime]::ParseExact($_.first_seen.Replace('T','').Replace('Z',''),'yyyy-MM-ddHH:mm:ss',$null)}},
        @{Name='Last_Seen';Expression={[datetime]::ParseExact($_.last_seen.Replace('T','').Replace('Z',''),'yyyy-MM-ddHH:mm:ss',$null)}},
        reduced_functionality_mode | ConvertTo-Csv -Delimiter ',' -NoTypeInformation).Replace('"','')
    
    # Display CSV File
    $FalconHostsCSV
    }
catch
    {
    $Message = "Error during convert to CSV file for FalconHosts - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }

# Export CSV
 try
    {   
    $FalconHostsCSV | Out-File -FilePath "$ExportFolder`/FalconHosts.csv" -Force
    }
catch
    {
    $Message = "Error during export of CSV file for FalconHosts - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }


#endregion Falcon Hosts 







#region Falcon Detection




#Get-FalconDetection
write-host "FALCON DETECTION EVENTS" -B White -f Blue
try
    {
    $FalconDetection = Get-FalconDetection -Detailed -All  
    $FalconDetection | sort created_timestamp -Descending
    }
catch
    {
    $Message = "Error during Get-FalconDetection - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }


# Convert To CSV
 try
    {
    $FalconDetectionCSV = $($FalconDetection | select `
    detection_id,
    @{Name='Detection_Creation_Date';Expression={[datetime]::ParseExact($_[0].created_timestamp.split('.')[0].Replace('T',''),'yyyy-MM-ddHH:mm:ss',$null)}},
    @{Name='HostName';Expression={$_.device.hostname}},
    @{Name='HostIP';Expression={$_.device.local_ip}},
    @{Name='DeviceID';Expression={$_.device.device_id}},
    @{Name='BehaviorID';Expression={$_.Behaviors.Behavior_id}},
    @{Name='Behavior_FileName';Expression={$_.Behaviors.filename}},
    @{Name='Behavior_FilePath';Expression={$_.Behaviors.filepath}},
    @{Name='Behavior_cmdline';Expression={$_.Behaviors.cmdline}},
    status,
    max_severity_displayname,
    email_sent | ConvertTo-Csv -Delimiter ',' -NoTypeInformation).Replace('"','')
    }
catch
    {
    $Message = "Error during convert to CSV file for FalconDetection - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }

# Export CSV
 try
    {   
    $FalconDetectionCSV | Out-File -FilePath "$ExportFolder`/FalconDetection.csv"
    }
catch
    {
    $Message = "Error during export of CSV file for FalconDetection - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }




#endregion Falcon Detection




#region Falcon Behavior

# Get-FalconBehavior (NB: Transform TimeStamp to more readable format with [datetime]::ParseExact)
write-host "FALCON BEHAVIOR EVENTS" -B White -f Blue

try
    {
    $FalconBehavior = Get-FalconBehavior | foreach {Get-FalconBehavior -Ids $_} | Select -property  behavior_id,display_name,objective,@{Name='BehaviorDate';Expression={[datetime]::ParseExact($_.timestamp.Replace('T','').replace('Z',''),'yyyy-MM-ddHH:mm:ss',$null)}},cmdline,filepath,user_name,incident_id,tactic_id,tactic,technique_id,technique | sort BehaviorDate -Descending
    $FalconBehavior
    }
catch
    {
    $Message = "Error during Get-FalconBehavior - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }


# Convert To CSV
 try
    {
    $FalconBehaviorCSV = $($FalconBehavior | select BehaviorDate,cmdline,filepath,user_name | ConvertTo-Csv -Delimiter ';' -NoTypeInformation).Replace('"','')
    }
catch
    {
    $Message = "Error during convert to CSV file for FalconBehavior - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }

# Export CSV
 try
    {   
    $FalconBehaviorCSV | Out-File -FilePath "$ExportFolder`/FalconBehavior.csv"
    }
catch
    {
    $Message = "Error during export of CSV file for FalconBehavior - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }



#endregion Falcon Behavior





#region Falcon Incident

write-host "FALCON INCIDENTS EVENTS" -B White -f Blue
try
    {
    $FalconIncidents= Get-FalconIncident -Detailed -All  
    $FalconIncidents | sort created -Descending
    }
catch
    {
    $Message = "Error during Get-FalconIncident - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }


# Convert To CSV
 try
    {
    $FalconIncidentsCSV = $($FalconIncidents | select `
    incident_id,
    @{Name='Creation_Date';Expression={[datetime]::ParseExact($_.created.Replace('T','').Replace('Z',''),'yyyy-MM-ddHH:mm:ss',$null)}},
    state,
    email_state  | ConvertTo-Csv -Delimiter ',' -NoTypeInformation).Replace('"','')



        

    }
catch
    {
    $Message = "Error during convert to CSV file for FalconIncident - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }

# Export CSV
 try
    {   
    $FalconIncidentsCSV | Out-File -FilePath "$ExportFolder`/FalconIncidents.csv"
    }
catch
    {
    $Message = "Error during export of CSV file for FalconIncidents - END OF SCRIPT"
    write-host -F Red $Message
    Write-Log -Message $Message -LogPath $LogFolder -LogName $Log
    EXIT 1
    }




#endregion Falcon Incident