Suspicious Service Principal creation activity

Back


Id	6852d9da-8015-4b95-8ecf-d9572ee0395d
Rulename	Suspicious Service Principal creation activity
Description	This alert will detect creation of an SPN, permissions granted, credentials created, activity and deletion of the SPN in a time frame (default 10 minutes)
Severity	Low
Tactics	CredentialAccess PrivilegeEscalation InitialAccess
Techniques	T1078 T1528
Required data connectors	AzureActiveDirectory
Kind	Scheduled
Query frequency	1h
Query period	1h10m
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/SuspiciousServicePrincipalcreationactivity.yaml
Version	1.0.4
Arm template	6852d9da-8015-4b95-8ecf-d9572ee0395d.json

KQL

let queryfrequency = 1h;
let wait_for_deletion = 10m;
let account_created =
  AuditLogs 
  | where ActivityDisplayName == "Add service principal"
  | where Result == "success"
  | extend AppID = tostring(AdditionalDetails[1].value)
  | extend creationTime = ActivityDateTime
  | extend CreatorUserPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)
  | extend CreatorIPAddress = tostring(parse_json(tostring(InitiatedBy.user)).ipAddress);
let account_activity =
  AADServicePrincipalSignInLogs
  | extend Activities = pack("ActivityTime", TimeGenerated ,"IpAddress", IPAddress, "ResourceDisplayName", ResourceDisplayName)
  | extend AppID = AppId
  | summarize make_list(Activities) by AppID;
let account_deleted =
  AuditLogs 
  | where OperationName == "Remove service principal"
  | where Result == "success"
  | extend AppID = tostring(AdditionalDetails[1].value)
  | extend deletionTime = ActivityDateTime
  | extend DeleterUserPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)
  | extend DeleterIPAddress = tostring(parse_json(tostring(InitiatedBy.user)).ipAddress);
let account_credentials =
  AuditLogs
  | where OperationName has_all ("Update application", "Certificates and secrets management")
  | where Result == "success"
  | extend AppID = tostring(AdditionalDetails[1].value)
  | extend credentialCreationTime = ActivityDateTime;
let roles_assigned =
  AuditLogs
  | where ActivityDisplayName == "Add app role assignment to service principal"
  | extend AppID = tostring(TargetResources[1].displayName)
  | extend AssignedRole =  iff(tostring(parse_json(tostring(TargetResources[0].modifiedProperties))[1].displayName)=="AppRole.Value", tostring(parse_json(tostring(parse_json(tostring(TargetResources[0].modifiedProperties))[1].newValue))),"")
  | extend AssignedRoles = pack("Role", AssignedRole)
  | summarize make_list(AssignedRoles) by AppID;
account_created
| where TimeGenerated between (ago(wait_for_deletion+queryfrequency)..ago(wait_for_deletion))
| join kind= inner (account_activity) on AppID
| join kind= inner (account_deleted) on AppID
| join kind= inner (account_credentials) on AppID
| join kind= inner (roles_assigned) on AppID
| where deletionTime - creationTime between (time(0s)..wait_for_deletion)
| extend AliveTime = deletionTime - creationTime
| project AADTenantId, AppID, creationTime, deletionTime, CreatorUserPrincipalName, DeleterUserPrincipalName, CreatorIPAddress, DeleterIPAddress, list_Activities, list_AssignedRoles, AliveTime
| extend CreatorName = tostring(split(CreatorUserPrincipalName, "@")[0]), CreatorUPNSuffix = tostring(split(CreatorUserPrincipalName, "@")[1])
| extend DeleterName = tostring(split(DeleterUserPrincipalName, "@")[0]), DeleterSuffix = tostring(split(DeleterUserPrincipalName, "@")[1])

YAML

version: 1.0.4
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Microsoft Entra ID/Analytic Rules/SuspiciousServicePrincipalcreationactivity.yaml
status: Available
description: |
    'This alert will detect creation of an SPN, permissions granted, credentials created, activity and deletion of the SPN in a time frame (default 10 minutes)'
queryFrequency: 1h
name: Suspicious Service Principal creation activity
tactics:
- CredentialAccess
- PrivilegeEscalation
- InitialAccess
triggerThreshold: 0
id: 6852d9da-8015-4b95-8ecf-d9572ee0395d
query: |
  let queryfrequency = 1h;
  let wait_for_deletion = 10m;
  let account_created =
    AuditLogs 
    | where ActivityDisplayName == "Add service principal"
    | where Result == "success"
    | extend AppID = tostring(AdditionalDetails[1].value)
    | extend creationTime = ActivityDateTime
    | extend CreatorUserPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)
    | extend CreatorIPAddress = tostring(parse_json(tostring(InitiatedBy.user)).ipAddress);
  let account_activity =
    AADServicePrincipalSignInLogs
    | extend Activities = pack("ActivityTime", TimeGenerated ,"IpAddress", IPAddress, "ResourceDisplayName", ResourceDisplayName)
    | extend AppID = AppId
    | summarize make_list(Activities) by AppID;
  let account_deleted =
    AuditLogs 
    | where OperationName == "Remove service principal"
    | where Result == "success"
    | extend AppID = tostring(AdditionalDetails[1].value)
    | extend deletionTime = ActivityDateTime
    | extend DeleterUserPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)
    | extend DeleterIPAddress = tostring(parse_json(tostring(InitiatedBy.user)).ipAddress);
  let account_credentials =
    AuditLogs
    | where OperationName has_all ("Update application", "Certificates and secrets management")
    | where Result == "success"
    | extend AppID = tostring(AdditionalDetails[1].value)
    | extend credentialCreationTime = ActivityDateTime;
  let roles_assigned =
    AuditLogs
    | where ActivityDisplayName == "Add app role assignment to service principal"
    | extend AppID = tostring(TargetResources[1].displayName)
    | extend AssignedRole =  iff(tostring(parse_json(tostring(TargetResources[0].modifiedProperties))[1].displayName)=="AppRole.Value", tostring(parse_json(tostring(parse_json(tostring(TargetResources[0].modifiedProperties))[1].newValue))),"")
    | extend AssignedRoles = pack("Role", AssignedRole)
    | summarize make_list(AssignedRoles) by AppID;
  account_created
  | where TimeGenerated between (ago(wait_for_deletion+queryfrequency)..ago(wait_for_deletion))
  | join kind= inner (account_activity) on AppID
  | join kind= inner (account_deleted) on AppID
  | join kind= inner (account_credentials) on AppID
  | join kind= inner (roles_assigned) on AppID
  | where deletionTime - creationTime between (time(0s)..wait_for_deletion)
  | extend AliveTime = deletionTime - creationTime
  | project AADTenantId, AppID, creationTime, deletionTime, CreatorUserPrincipalName, DeleterUserPrincipalName, CreatorIPAddress, DeleterIPAddress, list_Activities, list_AssignedRoles, AliveTime
  | extend CreatorName = tostring(split(CreatorUserPrincipalName, "@")[0]), CreatorUPNSuffix = tostring(split(CreatorUserPrincipalName, "@")[1])
  | extend DeleterName = tostring(split(DeleterUserPrincipalName, "@")[0]), DeleterSuffix = tostring(split(DeleterUserPrincipalName, "@")[1])  
severity: Low
queryPeriod: 1h10m
entityMappings:
- fieldMappings:
  - columnName: CreatorUserPrincipalName
    identifier: FullName
  - columnName: CreatorName
    identifier: Name
  - columnName: CreatorUPNSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: DeleterUserPrincipalName
    identifier: FullName
  - columnName: DeleterName
    identifier: Name
  - columnName: DeleterSuffix
    identifier: UPNSuffix
  entityType: Account
- fieldMappings:
  - columnName: CreatorIPAddress
    identifier: Address
  entityType: IP
- fieldMappings:
  - columnName: DeleterIPAddress
    identifier: Address
  entityType: IP
relevantTechniques:
- T1078
- T1528
kind: Scheduled
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - AuditLogs
  - AADServicePrincipalSignInLogs

ARM