Detect Critical Alerts from Security Tools
SPLUNK detection rule by Gowthamaraj Rajendran, Patrick Bareiss, Bhavin Patel, Bryan Pluta, Splunk · Apache-2.0
The following analytic has been deprecated in favour of specific and dedicated product analytics such as "Microsoft Defender ATP Alerts". The following analytic is to detect high and critical alerts from endpoint security tools such as Microsoft Defender, Carbon Black, and Crowdstrike. This query aggregates and summarizes critical severity alerts from the Alerts data model, providing details such as the alert signature, application, description, source, destination, and timestamps, while applying custom filters and formatting for enhanced analysis in a SIEM environment.This capability allows security teams to efficiently allocate resources and maintain a strong security posture, while also supporting compliance with regulatory requirements by providing a clear record of critical security events. We tested these detections with logs from Microsoft Defender, however this detection should work for any security alerts that are ingested into the alerts data model. **Note** - We are dynamically creating the risk_score field based on the severity of the alert in the SPL and that supersedes the risk score set in the detection.
name: Detect Critical Alerts from Security Tools
id: 483e8a68-f2f7-45be-8fc9-bf725f0e22fd
version: 2
creation_date: '2024-07-24'
modification_date: '2026-05-13'
author: Gowthamaraj Rajendran, Patrick Bareiss, Bhavin Patel, Bryan Pluta, Splunk
status: removed
type: TTP
data_source:
- Windows Defender Alerts
- MS365 Defender Incident Alerts
description: The following analytic has been deprecated in favour of specific and dedicated product analytics such as "Microsoft Defender ATP Alerts". The following analytic is to detect high and critical alerts from endpoint security tools such as Microsoft Defender, Carbon Black, and Crowdstrike. This query aggregates and summarizes critical severity alerts from the Alerts data model, providing details such as the alert signature, application, description, source, destination, and timestamps, while applying custom filters and formatting for enhanced analysis in a SIEM environment.This capability allows security teams to efficiently allocate resources and maintain a strong security posture, while also supporting compliance with regulatory requirements by providing a clear record of critical security events. We tested these detections with logs from Microsoft Defender, however this detection should work for any security alerts that are ingested into the alerts data model. **Note** - We are dynamically creating the risk_score field based on the severity of the alert in the SPL and that supersedes the risk score set in the detection.
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(Alerts.description) as description values(Alerts.mitre_technique_id) as annotations.mitre_attack.mitre_technique_id values(Alerts.severity) as severity values(Alerts.type) as type values(Alerts.severity_id) as severity_id values(Alerts.signature) as signature values(Alerts.signature_id) as signature_id values(Alerts.dest) as dest from datamodel=Alerts where Alerts.severity IN ("high","critical") by Alerts.src Alerts.user Alerts.id Alerts.vendor sourcetype | `drop_dm_object_name("Alerts")` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | eval risk_score=case(severity="informational", 2, severity="low", 5, severity="medium", 10, severity="high", 50, severity="critical" , 100) | `detect_critical_alerts_from_security_tools_filter`'
how_to_implement: In order to properly run this search, you to ingest alerts data from other security products such as Crowdstrike, Microsoft Defender, or Carbon Black using appropriate TAs for that technology. Once ingested, the fields should be mapped to the Alerts data model. Make sure to apply transformation on the data if necessary. The risk_score field is used to calculate the risk score for the alerts and the mitre_technique_id field is used to map the alerts to the MITRE ATT&CK framework is dynamically created by the detection when this is triggered. These fields need not be set in the adaptive response actions.
known_false_positives: False positives may vary by endpoint protection tool; monitor and filter out the alerts that are not relevant to your environment.
references:
- https://techcommunity.microsoft.com/t5/microsoft-defender-for-cloud/accessing-microsoft-defender-for-cloud-alerts-in-splunk-using/ba-p/938228
- https://docs.splunk.com/Documentation/CIM/5.3.2/User/Alerts
- https://learn.microsoft.com/en-us/defender-endpoint/api/raw-data-export-event-hub
drilldown_searches:
- name: View the detection results for - "$dest$" and "$user$"
search: '%original_detection_search% | search dest = "$dest$" user = "$user$"'
earliest_offset: $info_min_time$
latest_offset: $info_max_time$
- name: View risk events for the last 7 days for - "$dest$" and "$user$"
search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
earliest_offset: $info_min_time$
latest_offset: $info_max_time$
rba:
message: $severity$ alert for $user$ from $sourcetype$ - $signature$
risk_objects:
- field: user
type: user
score: 50
- field: dest
type: system
score: 50
threat_objects: []
tags:
analytic_story:
- Critical Alerts
asset_type: Endpoint
atomic_guid: []
mitre_attack_id: []
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/suspicious_behaviour/alerts/AdvancedHunting.log
source: eventhub://windowsdefenderlogs
sourcetype: mscs:azure:eventhub:defender:advancedhunting
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/suspicious_behaviour/alerts/defender_incident_alerts.log
source: m365_defender_incident_alerts
sourcetype: ms365:defender:incident:alerts
deprecation_info:
reason: As discussed internally, this analytic was too generic for an analyst to do anything with it. It was deprecated in favor of the more specific approach provided by analytics such as Microsoft Defender ATP Alerts and Microsoft Defender Incident Alerts. Going forward analytics from leveraging alerts from vendors will have their specific analytics.
removed_in_version: 5.2.0
replacement_content:
- Microsoft Defender ATP Alerts
- Microsoft Defender Incident Alerts
CIRCL