Authentication Method Changed for Privileged Account

id: feb0a2fb-ae75-4343-8cbc-ed545f1da289
name: Authentication Method Changed for Privileged Account
description: |
  'Identifies authentication methods being changed for a privileged account. This could be an indication of an attacker adding an auth method to the account so they can have continued access.
  Ref : https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-privileged-accounts#things-to-monitor-1'
severity: High
requiredDataConnectors:
  - connectorId: AzureActiveDirectory
    dataTypes:
      - AuditLogs
  - connectorId: BehaviorAnalytics
    dataTypes:
      - IdentityInfo
queryFrequency: 2h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Persistence
relevantTechniques:
  - T1098
tags:
  - AADSecOpsGuide
query: |
    let VIPUsers = (IdentityInfo
    | where AssignedRoles contains "Admin"
    | summarize by tolower(AccountUPN));
    AuditLogs
    | where TimeGenerated > ago(2h)
    | where Category =~ "UserManagement"
    | where ActivityDisplayName =~ "User registered security info"
    | where LoggedByService =~ "Authentication Methods"
    | extend TargetUserPrincipalName = tostring(TargetResources[0].userPrincipalName)
    | where tolower(TargetUserPrincipalName) in (VIPUsers)
    | extend TargetAadUserId = tostring(TargetResources[0].id)
    | extend InitiatingUserPrincipalName = tostring(InitiatedBy.user.userPrincipalName)
    | extend InitiatingAadUserId = tostring(InitiatedBy.user.id)
    | extend InitiatingIPAddress = tostring(InitiatedBy.user.ipAddress)
    | extend TargetAccountName = tostring(split(TargetUserPrincipalName, "@")[0]), TargetAccountUPNSuffix = tostring(split(TargetUserPrincipalName, "@")[1])
    | extend InitiatingAccountName = tostring(split(InitiatingUserPrincipalName, "@")[0]), InitiatingAccountUPNSuffix = tostring(split(InitiatingUserPrincipalName, "@")[1])
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: TargetUserPrincipalName
      - identifier: Name
        columnName: TargetAccountName
      - identifier: UPNSuffix
        columnName: TargetAccountUPNSuffix
  - entityType: Account
    fieldMappings:
      - identifier: AadUserId
        columnName: TargetAadUserId
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: InitiatingUserPrincipalName
      - identifier: Name
        columnName: InitiatingAccountName
      - identifier: UPNSuffix
        columnName: InitiatingAccountUPNSuffix
  - entityType: Account
    fieldMappings:
      - identifier: AadUserId
        columnName: InitiatingAadUserId
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: InitiatingIPAddress
version: 1.0.5
kind: Scheduled