Windows List ENV Variables Via SET Command From Uncommon Parent

Original Source: [splunk source]
Name:Windows List ENV Variables Via SET Command From Uncommon Parent
id:aec157f4-8783-4584-aca6-754c4dc7fba9
version:2
date:2025-01-17
author:Teoderick Contreras, Splunk
status:production
type:Anomaly
Description:The following analytic identifies a suspicious process command line fetching environment variables using the cmd.exe "set" command, with a non-shell parent process. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and parent process names. This activity could be significant as it is commonly associated with malware like Qakbot, which uses this technique to gather system information. If confirmed malicious, this behavior could indicate that the parent process has been compromised, potentially allowing attackers to execute arbitrary commands, escalate privileges, or persist within the environment.
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_name="cmd.exe" Processes.process IN ("*/c set", "*/c \"set") AND NOT Processes.parent_process_name IN ("cmd.exe", "explorer.exe", "powershell*" "pwsh.exe") 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.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
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_list_env_variables_via_set_command_from_uncommon_parent_filter`


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:shell process that are not included in this search may cause False positive. Filter as needed.
References:
  -https://twitter.com/pr0xylife/status/1585612370441031680?s=46&t=Dc3CJi4AnM-8rNoacLbScg
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 ("$dest$") 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:'$info_max_time$'
tags:
  analytic_story:
    - 'Qakbot'
  asset_type:Endpoint
  mitre_attack_id:
    - 'T1055'
  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/malware/qakbot/qbot_wermgr/sysmon_wermgr.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None

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