Name:Windows Mshta Execution In Registry id:e13ceade-b673-4d34-adc4-4d9c01729753 version:3 date:2024-09-30 author:Teoderick Contreras, Splunk status:production type:TTP Description:The following analytic detects the execution of mshta.exe via registry entries to run malicious scripts. It leverages registry activity logs to identify entries containing "mshta," "javascript," "vbscript," or "WScript.Shell." This behavior is significant as it indicates potential fileless malware, such as Kovter, which uses encoded scripts in the registry to persist and execute without files. If confirmed malicious, this activity could allow attackers to maintain persistence, execute arbitrary code, and evade traditional file-based detection methods, posing a significant threat to system integrity and security. 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_value_data = "*mshta*" OR Registry.registry_value_data IN ("*javascript:*", "*vbscript:*","*WScript.Shell*") by Registry.registry_key_name Registry.registry_path Registry.registry_value_data Registry.action Registry.dest Registry.user| `drop_dm_object_name(Registry)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_mshta_execution_in_registry_filter`
how_to_implement:To successfully implement this search, you must be ingesting data that records registry activity from your hosts to populate the endpoint data model in the registry node. This is typically populated via endpoint detection-and-response product, such as Carbon Black or endpoint data sources, such as Sysmon. The data used for this search is typically generated via logs that report reads and writes to the registry. known_false_positives:unknown References: -https://redcanary.com/threat-detection-report/techniques/mshta/ -https://learn.microsoft.com/en-us/microsoft-365/security/intelligence/fileless-threats?view=o365-worldwide 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 ("$dest$", "$user$") 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: - 'Suspicious Windows Registry Activities' - 'Windows Persistence Techniques' asset_type:Endpoint confidence:90 impact:80 message:A registry $registry_path$ contains mshta $registry_value_data$ in $dest$ mitre_attack_id: - 'T1218.005' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'Registry.registry_key_name' - 'Registry.registry_path' - 'Registry.dest' - 'Registry.registry_value_data' - 'Registry.action' risk_score:72 security_domain:endpoint
