Detect and investigate Azure service principal abuse including privilege escalation, credential compromise, admin consent bypass, and unauthorized enumeration in Microsoft Entra ID environments.
Detect and investigate Azure service principal abuse including privilege escalation, credential compromise, admin consent bypass, and unauthorized enumeration in Microsoft Entra ID environments.
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.
When to Use
When investigating security incidents that require detecting azure service principal abuse
When building detection rules or threat hunting queries for this domain
When SOC analysts need structured procedures for this analysis type
When validating security monitoring coverage for related attack techniques
Detection Gaps & Validation
What silently slips past these AuditLogs queries:
Hard-coded modifiedProperties[1] index. The position of Role.DisplayName / AppRole.Value drifts per event — filter by the property displayName instead of an index, or you misread (or miss) Global Administrator grants.
Certificate credentials, not just secrets.Add service principal credentials with KeyType=AsymmetricX509Cert is cert-based persistence that secret-only filters skip.
App-role grants bypass user consent entirely.Add app role assignment to service principal granting Application.ReadWrite.All / RoleManagement.ReadWrite.Directory is application permission — it never appears in delegated-consent logs.
Enumeration detection depends on MicrosoftGraphActivityLogs. If that table isn't licensed/ingested, the /servicePrincipals enumeration query returns nothing and looks "clean."
Managed identities are service principals too (servicePrincipalType == ManagedIdentity) — baseline them or drown in FP.
Validate: confirm AuditLogs, AADServicePrincipalSignInLogs, and MicrosoftGraphActivityLogs all have rows in the last 24h; test by adding a throwaway secret to a test SP and confirming the rule fires; tune FP by excluding CI/CD app object IDs.
Prerequisites
Azure subscription with Microsoft Entra ID P2 license
Access to Azure AD Audit Logs and Sign-in Logs
Microsoft Sentinel or Splunk for SIEM-based detection
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:
Detection 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
Detection 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 Detection
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
AADServicePrincipalSignInLogs
| where ServicePrincipalId == "<target-sp-id>"
| project TimeGenerated, ServicePrincipalName, IPAddress, Location,
ResourceDisplayName, Status.errorCode
| sort by TimeGenerated desc
Preventive Controls
Restrict application registration
# Disable user ability to register applications
Update-MgPolicyAuthorizationPolicy -DefaultUserRolePermissions @{
AllowedToCreateApps = $false
}
Configure app consent policies
# Require admin approval for all app consent requests
New-MgPolicyPermissionGrantPolicy -Id "admin-only-consent" `
-DisplayName "Admin Only Consent" `
-Description "Only admins can consent to applications"
