Name:Windows Defender ASR or Threat Configuration Tamper id:d0c07718-19d1-4de2-aea9-e0ffff0ed986 version:6 date:None author:Nasreddine Bencherchali, Splunk status:production type:TTP Description:The following analytic detects the use of commands to disable Attack Surface Reduction (ASR) rules or change threat default actions in Windows Defender.
It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving "Add-MpPreference" or "Set-MpPreference".
This activity is significant because adversaries often use it to bypass Windows Defender, allowing malicious code to execute undetected.
If confirmed malicious, this behavior could enable attackers to evade antivirus detection, maintain persistence, and execute further malicious activities without interference from Windows Defender.
Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime
from datamodel=Endpoint.Processes where
Processes.process IN ("*Add-MpPreference *", "*Set-MpPreference *")
Processes.process IN ( "*-AttackSurfaceReductionRules_Actions*", "*-ThreatIDDefaultAction_Actions*" )
how_to_implement:The detection is based on data that originates from Endpoint Detection
and Response (EDR) agents. These agents are designed to provide security-related
telemetry from the endpoints where the agent is installed. To implement this search,
you must ingest logs that contain the process GUID, process name, and parent process.
Additionally, you must ingest complete command-line executions. These logs must
be processed using the appropriate Splunk Technology Add-ons that are specific to
the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint`
data model. Use the Splunk Common Information Model (CIM) to normalize the field
names and speed up the data modeling process.
known_false_positives:Certain administrative tasks may require the modification of ASR rules or threat actions due to FPs being generated. Investigate all attempts and filter as needed.
References: -https://learn.microsoft.com/en-us/powershell/module/defender/set-mppreference?view=windowsserver2025-ps#-attacksurfacereductionrules-actions -https://www.virustotal.com/gui/file/7e805617c313ec2fb59d86719c827074cb7dfbf8f0aa18194ac1ffe6c21c8967/behavior 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 ("$dest$", "$user$") | 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:'7d' latest_offset:'0' analytic_story:['Windows Defense Evasion Tactics']
