atomic-threat-coverage/Atomic_Threat_Coverage/Detection_Rules/sysmon_lethalhta.md

Title	MSHTA spwaned by SVCHOST as seen in LethalHTA
Description	Detects MSHTA.EXE spwaned by SVCHOST described in report
ATT&CK Tactic
ATT&CK Technique
Data Needed	DN_0003_1_windows_sysmon_process_creation
Trigger	There is no Trigger for this technique yet.
Severity Level	high
False Positives	Unknown
Development Status	experimental
References	https://codewhitesec.blogspot.com/2018/07/lethalhta.html
Author	Markus Neis

Detection Rules

Sigma rule

title: MSHTA spwaned by SVCHOST as seen in LethalHTA 
status: experimental
description: Detects MSHTA.EXE spwaned by SVCHOST described in report
references:
    - https://codewhitesec.blogspot.com/2018/07/lethalhta.html
author: Markus Neis
date: 2018/06/07
logsource:
    product: windows
    service: sysmon
detection:
    selection:
        EventID: 1
        ParentImage: '*\svchost.exe'
        Image: '*\mshta.exe'
    condition: selection
falsepositives:
    - Unknown
level: high

Kibana query

(EventID:"1" AND ParentImage.keyword:*\\\\svchost.exe AND Image.keyword:*\\\\mshta.exe)

X-Pack Watcher

curl -s -XPUT -H \'Content-Type: application/json\' --data-binary @- localhost:9200/_xpack/watcher/watch/MSHTA-spwaned-by-SVCHOST-as-seen-in-LethalHTA <<EOF\n{\n  "trigger": {\n    "schedule": {\n      "interval": "30m"\n    }\n  },\n  "input": {\n    "search": {\n      "request": {\n        "body": {\n          "size": 0,\n          "query": {\n            "query_string": {\n              "query": "(EventID:\\"1\\" AND ParentImage.keyword:*\\\\\\\\svchost.exe AND Image.keyword:*\\\\\\\\mshta.exe)",\n              "analyze_wildcard": true\n            }\n          }\n        },\n        "indices": []\n      }\n    }\n  },\n  "condition": {\n    "compare": {\n      "ctx.payload.hits.total": {\n        "not_eq": 0\n      }\n    }\n  },\n  "actions": {\n    "send_email": {\n      "email": {\n        "to": null,\n        "subject": "Sigma Rule \'MSHTA spwaned by SVCHOST as seen in LethalHTA\'",\n        "body": "Hits:\\n{{#ctx.payload.hits.hits}}{{_source}}\\n================================================================================\\n{{/ctx.payload.hits.hits}}",\n        "attachments": {\n          "data.json": {\n            "data": {\n              "format": "json"\n            }\n          }\n        }\n      }\n    }\n  }\n}\nEOF\n

Graylog

(EventID:"1" AND ParentImage:"*\\\\svchost.exe" AND Image:"*\\\\mshta.exe")