Authentications of Privileged Accounts Outside of Expected Controls

id: af435ca1-fb70-4de1-92c1-7435c48482a9
name: Authentications of Privileged Accounts Outside of Expected Controls
description: |
  'Detects when a privileged user account successfully authenticates from a location, device or ASN that another admin has not logged in from in the last 7 days.
    Privileged accounts are a key target for threat actors, monitoring for logins from these accounts that deviate from normal activity can help identify compromised accounts.
    Authentication attempts should be investigated to ensure the activity was legitimate and if there is other similar activity.
    Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#monitoring-for-successful-unusual-sign-ins'
severity: Medium
requiredDataConnectors:
  - connectorId: AzureActiveDirectory
    dataTypes:
      - SigninLogs
  - connectorId: BehaviorAnalytics
    dataTypes:
      - BehaviorAnalytics
  - connectorId: BehaviorAnalytics
    dataTypes:
      - IdentityInfo
queryFrequency: 1d
queryPeriod: 7d
triggerOperator: gt
triggerThreshold: 0
tactics:
  - InitialAccess
relevantTechniques:
  - T1078.004
tags:
  - AADSecOpsGuide
query: |
  let admin_users = (IdentityInfo
    | summarize arg_max(TimeGenerated, *) by AccountUPN
    | where AssignedRoles contains "admin"
    | summarize by tolower(AccountUPN));
    let admin_asn = (SigninLogs
    | where TimeGenerated between (ago(7d)..ago(1d))
    | where tolower(UserPrincipalName) in (admin_users)
    | summarize by AutonomousSystemNumber);
    let admin_locations = (SigninLogs
    | where TimeGenerated between (ago(7d)..ago(1d))
    | where tolower(UserPrincipalName) in (admin_users)
    | summarize by Location);
    let admin_devices = (SigninLogs
    | where TimeGenerated between (ago(7d)..ago(1d))
    | where tolower(UserPrincipalName) in (admin_users)
    | extend deviceId = tostring(DeviceDetail.deviceId)
    | where isnotempty(deviceId)
    | summarize by deviceId);
    SigninLogs
    | where TimeGenerated > ago(1d)
    | where ResultType == 0
    | where tolower(UserPrincipalName) in (admin_users)
    | extend deviceId = tostring(DeviceDetail.deviceId)
    | where AutonomousSystemNumber !in (admin_asn) and deviceId !in (admin_devices) and Location !in (admin_locations)
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: FullName
        columnName: UserPrincipalName
version: 1.0.2
kind: Scheduled
metadata:
    source:
        kind: Community
    author:
        name: Pete Bryan
    support:
        tier: Community
    categories:
        domains: [ "Security - Others", "Identity" ]