Name:Windows Process Accessing IronLanguages Repository On GitHub id:bcdc2543-8c33-44c8-a723-5b7b93e06788 version:1 date:None author:Onur Mustafa Erdogan, Splunk status:production type:Anomaly Description:The following analytic identifies a process command line referencing the IronLanguages GitHub repository, which hosts .NET implementation of popular scripting engines.
Adversaries have downloaded these .NET implementations to avoid getting detected by security controls while executing their payloads.
This activity is uncommon in typical enterprise environments outside of software development contexts. 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
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:Software developers or DevOps personnel may legitimately clone or download the IronPython repository from GitHub for development purposes.
Filter as needed based on known developer hosts or users in your environment. References: -https://packetwatch.com/resources/threat-profile/clickfix-abuses-finger-to-deliver-castleloader -https://github.com/IronLanguages/ironpython3 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:['Compromised Windows Host', 'Fake CAPTCHA Campaigns', 'Ingress Tool Transfer', 'Windows Post-Exploitation']