Detection rules › Splunk

Azure Active Directory High Risk Sign-in

Status
production
Severity
medium
Group by
aws::recipientAccountId, category, dest, src, user, vendor_product
Author
Mauricio Velazco, Gowthamaraj Rajendran, Splunk
Source
github.com/splunk/security_content

The following analytic detects high-risk sign-in attempts against Azure Active Directory, identified by Azure Identity Protection. It leverages the RiskyUsers and UserRiskEvents log categories from Azure AD events ingested via EventHub. This activity is significant as it indicates potentially compromised accounts, flagged by heuristics and machine learning. If confirmed malicious, attackers could gain unauthorized access to sensitive resources, leading to data breaches or further exploitation within the environment.

Known false positives

  • Details for the risk calculation algorithm used by Identity Protection are unknown and may be prone to false positives.

MITRE ATT&CK coverage

Rule body

name: Azure Active Directory High Risk Sign-in
id: 1ecff169-26d7-4161-9a7b-2ac4c8e61bea
version: 14
creation_date: '2022-07-11'
modification_date: '2026-05-13'
author: Mauricio Velazco, Gowthamaraj Rajendran, Splunk
status: production
type: TTP
description: The following analytic detects high-risk sign-in attempts against Azure Active Directory, identified by Azure Identity Protection. It leverages the RiskyUsers and UserRiskEvents log categories from Azure AD events ingested via EventHub. This activity is significant as it indicates potentially compromised accounts, flagged by heuristics and machine learning. If confirmed malicious, attackers could gain unauthorized access to sensitive resources, leading to data breaches or further exploitation within the environment.
data_source:
    - Azure Active Directory
search: |-
    `azure_monitor_aad` category=UserRiskEvents properties.riskLevel=high
      | fillnull
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY dest user src
           vendor_account vendor_product category
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `azure_active_directory_high_risk_sign_in_filter`
how_to_implement: You must install the latest version of Splunk Add-on for Microsoft Cloud Services from Splunkbase (https://splunkbase.splunk.com/app/3110/#/details). You must be ingesting Azure Active Directory events into your Splunk environment through an EventHub. Specifically, this analytic leverages the RiskyUsers and UserRiskEvents log category in the azure:monitor:aad sourcetype.
known_false_positives: Details for the risk calculation algorithm used by Identity Protection are unknown and may be prone to false positives.
references:
    - https://attack.mitre.org/techniques/T1110/003/
    - https://docs.microsoft.com/en-us/security/compass/incident-response-playbook-password-spray
    - https://docs.microsoft.com/en-us/azure/active-directory/identity-protection/overview-identity-protection
    - https://docs.microsoft.com/en-us/azure/active-directory/identity-protection/concept-identity-protection-risks
finding:
    title: A high risk event was identified by Identify Protection for user $user$
    entity:
        field: user
        type: user
        score: 50
threat_objects:
    - field: src
      type: ip_address
analytic_story:
    - Azure Active Directory Account Takeover
asset_type: Azure Active Directory
mitre_attack_id:
    - T1110.003
    - T1586.003
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: cloud
security_domain: identity

Stages and Predicates

Stage 1: search

`azure_monitor_aad` category=UserRiskEvents properties.riskLevel=high

Stage 2: fillnull

| fillnull

Stage 3: stats

| stats count min(_time) as firstTime max(_time) as lastTime
    BY dest user src
       vendor_account vendor_product category

Stage 4: search

| `security_content_ctime(firstTime)`

Stage 5: search

| `security_content_ctime(lastTime)`

Stage 6: search

| `azure_active_directory_high_risk_sign_in_filter`

Indicators

These rows show field, operator, and value matches.