Elastic
Start free trial
Loading

Suspicious Script Object Execution

Elastic Stack Serverless Security

Identifies scrobj.dll loaded into unusual Microsoft processes. This usually means a malicious scriptlet is being executed in the target process.

Rule type: eql

Rule indices:

  • logs-endpoint.events.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Defense Evasion

Version: 6

Rule authors:

  • Elastic

Rule license: Elastic License v2

Rule query

sequence by process.entity_id with maxspan=2m
  [process where event.type == "start"
   and (process.code_signature.subject_name in ("Microsoft Corporation", "Microsoft Windows") and
   process.code_signature.trusted == true) and
     not process.executable : (
       "?:\\Windows\\System32\\cscript.exe",
       "?:\\Windows\\SysWOW64\\cscript.exe",
       "?:\\Program Files (x86)\\Internet Explorer\\iexplore.exe",
       "?:\\Program Files\\Internet Explorer\\iexplore.exe",
       "?:\\Windows\\SystemApps\\Microsoft.MicrosoftEdge_*\\MicrosoftEdge.exe",
       "?:\\Windows\\system32\\msiexec.exe",
       "?:\\Windows\\SysWOW64\\msiexec.exe",
       "?:\\Windows\\System32\\smartscreen.exe",
       "?:\\Windows\\system32\\taskhostw.exe",
       "?:\\windows\\system32\\inetsrv\\w3wp.exe",
       "?:\\windows\\SysWOW64\\inetsrv\\w3wp.exe",
       "?:\\Windows\\system32\\wscript.exe",
       "?:\\Windows\\SysWOW64\\wscript.exe",
       "?:\\Windows\\system32\\mobsync.exe",
       "?:\\Windows\\SysWOW64\\mobsync.exe",
       "?:\\Windows\\System32\\cmd.exe",
       "?:\\Windows\\SysWOW64\\cmd.exe")]
  [library where event.type == "start" and dll.name : "scrobj.dll"]

Framework: MITRE ATT&CKTM