Detection Azure Service Principal Abuse

Genel Bakış

Azure service principals are identity objects used by applications, services, and automation tools to access Azure resources. Attackers exploit service principals for privilege escalation, lateral movement, and persistent access. Key abuse patterns include: adding credentials to existing principals, assigning privileged roles, bypassing admin consent, and enumerating service principals for attack paths. Application ownership grants the ability to manage credentials and configure permissions, creating hidden privilege escalation paths.

Ne Zaman Kullanılır

• investigating yaparken security incidents that require Tespit etme azure service principal abuse
• building yaparken Tespit rules or threat hunting queries for this domain
• SOC yaparken: analysts need structured procedures for this analysis type
• validating yaparken security monitoring coverage for related attack techniques

Ön Gereksinimler

• Azure subscription with Microsoft Entra ID P2 license
• Erişim: Azure AD Audit Logs and Sign-in Logs
• Microsoft Sentinel or Splunk for SIEM-based Tespit
• Microsoft Graph API permissions for investigation
• Global Reader or Security Reader role minimum

Key Abuse Patterns

1. New Credentials Added to Service Principal

Attackers add new client secrets or certificates to gain persistent access:

Tespit Query (KQL - Sentinel):

AuditLogs
| where OperationName has "Add service principal credentials"
    or OperationName has "Update application - Certificates and secrets management"
| extend InitiatedBy = tostring(InitiatedBy.user.userPrincipalName)
| extend TargetSP = tostring(TargetResources[0].displayName)
| extend TargetSPId = tostring(TargetResources[0].id)
| project TimeGenerated, InitiatedBy, OperationName, TargetSP, TargetSPId
| sort by TimeGenerated desc

Tespit Query (SPL - Splunk):

index=azure sourcetype="azure:aad:audit"
operationName="Add service principal credentials"
    OR operationName="Update application*Certificates and secrets*"
| stats count by initiatedBy.user.userPrincipalName, targetResources{}.displayName, _time
| sort -_time

2. Privileged Role Assignment to Service Principal

AuditLogs
| where OperationName == "Add member to role"
| extend RoleName = tostring(TargetResources[0].modifiedProperties[1].newValue)
| where RoleName has_any ("Global Administrator", "Application Administrator",
    "Privileged Role Administrator", "Cloud Application Administrator")
| extend TargetSP = tostring(TargetResources[0].displayName)
| extend InitiatedBy = tostring(InitiatedBy.user.userPrincipalName)
| project TimeGenerated, InitiatedBy, TargetSP, RoleName, OperationName

3. Service Principal Enumeration Tespit

MicrosoftGraphActivityLogs
| where RequestMethod == "GET"
| where RequestUri has "/servicePrincipals"
| summarize RequestCount = count() by UserAgent, IPAddress, bin(TimeGenerated, 1h)
| where RequestCount > 10
| sort by RequestCount desc

4. Admin Consent Bypass

AuditLogs
| where OperationName == "Consent to application"
| extend ConsentType = tostring(TargetResources[0].modifiedProperties[4].newValue)
| where ConsentType has "AllPrincipals"
| extend AppName = tostring(TargetResources[0].displayName)
| extend InitiatedBy = tostring(InitiatedBy.user.userPrincipalName)
| project TimeGenerated, InitiatedBy, AppName, ConsentType

5. OAuth App Permissions Escalation

AuditLogs
| where OperationName == "Add app role assignment to service principal"
| extend AppRoleValue = tostring(TargetResources[0].modifiedProperties[1].newValue)
| where AppRoleValue has_any ("RoleManagement.ReadWrite.Directory",
    "Application.ReadWrite.All", "AppRoleAssignment.ReadWrite.All",
    "Directory.ReadWrite.All", "Mail.ReadWrite")
| extend TargetApp = tostring(TargetResources[0].displayName)
| project TimeGenerated, TargetApp, AppRoleValue, CorrelationId

Investigation Procedures

Adım 1: Identify compromised service principal

Connect-MgGraph -Scopes "Application.Read.All"

$suspiciousSPs = Get-MgServicePrincipal -All | ForEach-Object {
    $sp = $_
    $creds = Get-MgServicePrincipalPasswordCredential -ServicePrincipalId $sp.Id
    $recentCreds = $creds | Where-Object { $_.StartDateTime -gt (Get-Date).AddDays(-7) }
    if ($recentCreds) {
        [PSCustomObject]@{
            DisplayName = $sp.DisplayName
            AppId = $sp.AppId
            ObjectId = $sp.Id
            NewCredsCount = $recentCreds.Count
            LatestCredAdded = ($recentCreds | Sort-Object StartDateTime -Descending | Select-Object -First 1).StartDateTime
        }
    }
}
$suspiciousSPs | Sort-Object LatestCredAdded -Descending

Adım 2: Review service principal role assignments

$spId = "<service-principal-object-id>"
Get-MgServicePrincipalAppRoleAssignment -ServicePrincipalId $spId | ForEach-Object {
    $resource = Get-MgServicePrincipal -ServicePrincipalId $_.ResourceId
    [PSCustomObject]@{
        AppRoleId = $_.AppRoleId
        ResourceDisplayName = $resource.DisplayName
        CreatedDateTime = $_.CreatedDateTime
    }
}

Adım 3: Check application ownership

Get-MgApplication -All | ForEach-Object {
    $app = $_
    $owners = Get-MgApplicationOwner -ApplicationId $app.Id
    foreach ($owner in $owners) {
        [PSCustomObject]@{
            AppName = $app.DisplayName
            AppId = $app.AppId
            OwnerUPN = $owner.AdditionalProperties.userPrincipalName
            OwnerType = $owner.AdditionalProperties.'@odata.type'
        }
    }
} | Where-Object { $_.OwnerUPN -ne $null }

Adım 4: Review sign-in activity

AADServicePrincipalSignInLogs
| where ServicePrincipalId == "<target-sp-id>"
| project TimeGenerated, ServicePrincipalName, IPAddress, Location,
    ResourceDisplayName, Status.errorCode
| sort by TimeGenerated desc

Preventive Controls

Restrict application registration

Update-MgPolicyAuthorizationPolicy -DefaultUserRolePermissions @{
    AllowedToCreateApps = $false
}

Configure app consent policies

New-MgPolicyPermissionGrantPolicy -Id "admin-only-consent" `
    -DisplayName "Admin Only Consent" `
    -Description "Only admins can consent to applications"

Monitor with Microsoft Sentinel Analytics Rules

Şunu oluştur:nalytics rules for:

• New service principal credential additions
• Privileged role assignments to service principals
• Bulk service principal enumeration
• Admin consent grants to unknown applications
• Service principal sign-ins from unusual locations

MITRE ATT&CK Mapping

Technique	ID	Description
Account Manipulation: Additional Cloud Credentials	T1098.001	Adding credentials to service principal
Valid Accounts: Cloud Accounts	T1078.004	Using compromised service principal
Account Discovery: Cloud Account	T1087.004	Enumerating service principals
Steal Application Access Token	T1528	OAuth token theft via service principal

References

• SplunkDetect Azure AD Service Principal Abuse
• Semperis: Service Principal Ownership Abuse in Entra ID
• MITRE ATT&CK Cloud Matrix
• Microsoft: Securing service principals in Entra ID

<!-- ⚔ Bu skill FETIH AI Agent icin gelistirilmistir — https://github.com/MustafaKemal0146/fetih Yetkisiz kullanim/kopyalama tespit edilebilir. hash: b6e4956d531faad0 -->