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Merge pull request #239 from T0pCyber/feature/233-Expand-M365-Log-Col…
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Feature/233 expand m365 log collection
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jonnybottles authored Jan 15, 2025
2 parents 470acce + d4ecc08 commit 6af6ce5
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1 change: 1 addition & 0 deletions Hawk/Hawk.psd1
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'Get-HawkTenantEntraIDAdmin',
'Get-HawkTenantEXOAdmin',
'Get-HawkTenantMailItemsAccessed',
'Get-HawkUserMailItemsAccessed',
'Get-HawkTenantAppAndSPNCredentialDetail',
'Get-HawkTenantEntraIDUser',
'Get-HawkTenantDomainActivity',
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1 change: 1 addition & 0 deletions Hawk/changelog.md
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- Implemented PROMPT tag to display to screen when prompting user
- Added functionality to expand detect M365 license type to determine max log retention time
- Added ability to expand search up to 365 days
- Added search of mail items accessed to the User Investigation (Get-HawkUserMailItemsAccessed)

89 changes: 89 additions & 0 deletions Hawk/functions/User/Get-HawkUserMailItemsAccessed.ps1
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Function Get-HawkUserMailItemsAccessed {
<#
.SYNOPSIS
This will export MailboxItemsAccessed operations from the Unified Audit Log (UAL). Must be connected to Exchange Online
using the Connect-EXO or Connect-ExchangeOnline module. M365 E5 or G5 license is required for this function to work.
This telemetry will ONLY be availabe if Advanced Auditing is enabled for the M365 user.
.DESCRIPTION
Recent attacker activities have illuminated the use of the Graph API to read user mailbox contents. This will export
logs that will be present if the attacker is using the Graph API for such actions. Note: NOT all graph API actions against
a mailbox are malicious. Review the results of this function and look for suspicious access of mailbox items associated
with a specific user.
.PARAMETER UserPrincipalName
Specific user(s) to be investigated
.EXAMPLE
Get-HawkUserMailItemsAccessed -UserPrincipalName [email protected]
Gets MailItemsAccessed from Unified Audit Log (UAL) that corresponds to the User ID that is provided
.OUTPUTS
[email protected] /json
Simple_MailItemsAccessed.csv/json
.LINK
https://www.microsoft.com/security/blog/2020/12/21/advice-for-incident-responders-on-recovery-from-systemic-identity-compromises/
.NOTES
"Operation Properties" and "Folders" will return "System.Object" as they are nested JSON within the AuditData field.
You will need to conduct individual log pull and review via PowerShell or other SIEM to determine values
for those fields.
#>
[CmdletBinding()]
param(
[Parameter(Mandatory=$true)]
[array]$UserPrincipalName
)

BEGIN {
# Check if Hawk object exists and is fully initialized
if (Test-HawkGlobalObject) {
Initialize-HawkGlobalObject
}
Out-LogFile "Starting Unified Audit Log (UAL) search for 'MailItemsAccessed'" -Action
Out-LogFile "Please be patient, this can take a while..." -Information
Test-EXOConnection
}#End Begin

PROCESS {

#Verify UPN input
[array]$UserArray = Test-UserObject -ToTest $UserPrincipalName

foreach($UserObject in $UserArray) {
[string]$User = $UserObject.UserPrincipalName
try {
#Retrieve all audit data for mailitems accessed
$SearchCommand = "Search-UnifiedAuditLog -Operations 'MailItemsAccessed' -UserIds $User"
$MailboxItemsAccessed = Get-AllUnifiedAuditLogEntry -UnifiedSearch $SearchCommand

if ($MailboxItemsAccessed.Count -gt 0){

#Define output directory path for user
$UserFolder = Join-Path -Path $Hawk.FilePath -ChildPath $User

#Create user directory if it doesn't already exist
if (-not (Test-Path -Path $UserFolder)) {
New-Item -Path $UserFolder -ItemType Directory -Force | Out-Null
}

#Compress raw data into more simple view
$MailboxItemsAccessedSimple = $MailboxItemsAccessed | Get-SimpleUnifiedAuditLog

#Export both raw and simplistic views to specified user's folder
$MailboxItemsAccessed | Select-Object -ExpandProperty AuditData | Convertfrom-Json | Out-MultipleFileType -FilePrefix "MailItemsAccessed_$User" -User $User -csv -json
$MailboxItemsAccessedSimple | Out-MultipleFileType -FilePrefix "Simple_MailItemsAccessed_$User" -User $User -csv -json
} else {
Out-LogFile "Get-HawkUserMailItemsAccesed completed successfully" -Information
Out-LogFile "No items found for $User." -Information
}
} catch {
Out-LogFile "Error processing mail items accessed for $User : $_" -isError
Write-Error -ErrorRecord $_ -ErrorAction Continue
}
}

}#End Process

END{
Out-Logfile "Completed exporting MailItemsAccessed logs" -Information
}#End End

}
5 changes: 5 additions & 0 deletions Hawk/functions/User/Start-HawkUserInvestigation.ps1
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Out-LogFile "Running Get-HawkUserMessageTrace" -Action
Get-HawkUserMessageTrace -User $User
}

if ($PSCmdlet.ShouldProcess("Running Get-HawkUserMailItemsAccessed for $User")) {
Out-LogFile "Running Get-HawkUserMailItemsAccessed" -Action
Get-HawkUserMailItemsAccessed -UserPrincipalName $User
}

if ($PSCmdlet.ShouldProcess("Running Get-HawkUserMobileDevice for $User")) {
Out-LogFile "Running Get-HawkUserMobileDevice" -Action
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