Name:Windows Proxy Via Registry id:0270455b-1385-4579-9ac5-e77046c508ae version:4 date:2024-12-08 author:Teoderick Contreras, Splunk status:production type:Anomaly Description:The following analytic detects the modification of registry keys related to the Windows Proxy settings via netsh.exe. It leverages data from the Endpoint.Registry data model, focusing on changes to the registry path "*\\System\\CurrentControlSet\\Services\\PortProxy\\v4tov4\\tcp*". This activity is significant because netsh.exe can be used to establish a persistent proxy, potentially allowing an attacker to execute a helper DLL whenever netsh.exe runs. If confirmed malicious, this could enable the attacker to maintain persistence, manipulate network configurations, and potentially exfiltrate data or further compromise the system. Data_source:
-Sysmon EventID 12
-Sysmon EventID 13
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry where Registry.registry_path ="*\\System\\CurrentControlSet\\Services\\PortProxy\\v4tov4\\tcp*" by Registry.registry_path Registry.registry_key_name Registry.registry_value_name Registry.action Registry.dest Registry.user | `security_content_ctime(lastTime)` | `security_content_ctime(firstTime)` | `drop_dm_object_name(Registry)` | `windows_proxy_via_registry_filter`
how_to_implement:To successfully implement this search, you need to be ingesting logs with the registry value name, registry path, and registry value data from your endpoints. If you are using Sysmon, you must have at least version 2.0 of the official Sysmon TA. https://splunkbase.splunk.com/app/5709 known_false_positives:unknown References: -https://www.microsoft.com/en-us/security/blog/2023/05/24/volt-typhoon-targets-us-critical-infrastructure-with-living-off-the-land-techniques/ 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: - 'Volt Typhoon' asset_type:Endpoint atomic_guid: - 'b8223ea9-4be2-44a6-b50a-9657a3d4e72a' confidence:70 impact:70 message:A registry modification for port proxy in$dest$ mitre_attack_id: - 'T1090.001' - 'T1090' observable: name:'dest' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' risk_score:49 required_fields: - '_time' - 'Registry.registry_key_name' - 'Registry.registry_path' - 'Registry.user' - 'Registry.dest' - 'Registry.registry_value_name' - 'Registry.action' - 'Registry.registry_value_data' security_domain:endpoint
