Name:Windows Defender MpClient.dll Loaded by Non-Defender Process id:20f72601-2a92-47bc-8776-177671bbe189 version:1 date:None author:Onur Mustafa Erdogan, Splunk status:production type:Anomaly Description:The following analytic detects mpclient.dll, the Windows Defender client API library, being loaded by a process that is not part of the Windows Defender platform.
mpclient.dll exposes the API surface used to drive on-demand Defender scans (IOAV, MpScan). In the ShieldBreak exploit, the attacker binary loads mpclient.dll directly and calls its scan APIs against an object-manager path in order to trigger a Defender scan against attacker-controlled content as part of a race condition targeting Defender's placeholder-hydration behavior.
If confirmed malicious, this activity indicates an attempt to weaponize Windows Defender's own scanning pipeline for local privilege escalation. Data_source:
-Sysmon EventID 7
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where
Processes.loaded_file="mpclient.dll" NOT Processes.user IN ("* SERVICE", "SYSTEM") NOT Processes.process_path="*\MpCmdRun.exe" Processes.process_path IN ( "*:\\AppData\\Local\\Temp\\*", "*:\\Perflogs\\*", "*:\\ProgramData\\*", "*:\\Temp\\*", "*:\\Users\\*", "*:\\Windows\\Tasks\\*" ) by Processes.action Processes.dest Processes.original_file_name Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path Processes.loaded_file Processes.process Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
how_to_implement:To successfully implement this search, you need to be ingesting logs with the driver/module loaded from your endpoints.
If you are using Sysmon, configuration must explicitly include image loading events targeting mpclient.dll. known_false_positives:Third-party security products or custom AV-integration tooling that legitimately calls into the Defender client API may load mpclient.dll outside the Defender platform directories. Filter as necessary for your environment. References: -https://www.cyderes.com/howler-cell/rogueplanet-windows-zero-day -https://www.threatlocker.com/blog/nightmareeclipse-releases-new-poc-shieldbreak-exploits-same-weakness-as-rogueplanet drilldown_searches: name:'View the detection results for - "$dest$"' search:'%original_detection_search% | search dest = "$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | 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:['RoguePlanet']
