splunk-security_content/detections/endpoint/detect_mshta_renamed.yml

name: Detect mshta renamed
id: 8f45fcf0-5b68-11eb-ae93-0242ac130002
version: 3
date: '2022-04-07'
author: Michael Haag, Splunk
type: Hunting
datamodel:
- Endpoint
description: The following analytic identifies renamed instances of mshta.exe executing.
  Mshta.exe is natively found in C:\Windows\system32 and C:\Windows\syswow64. This
  analytic utilizes the internal name of the PE to identify if is the legitimate mshta
  binary. Further analysis should be performed to review the executed content and
  validation it is the real mshta.
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where Processes.process_name!=mshta.exe AND Processes.original_file_name=MSHTA.EXE by Processes.dest
  Processes.user Processes.parent_process_name Processes.process_name Processes.process
  Processes.process_id Processes.parent_process_id Processes.original_file_name |
  `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
  | `detect_mshta_renamed_filter`'
how_to_implement: To successfully implement this search you need to be ingesting information
  on process that include the name of the process responsible for the changes from
  your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition,
  confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
  endpoint product.
known_false_positives: Although unlikely, some legitimate applications may use a moved
  copy of mshta.exe, but never renamed, triggering a false positive.
references:
- https://github.com/redcanaryco/AtomicTestHarnesses
- https://redcanary.com/blog/introducing-atomictestharnesses/
tags:
  analytic_story:
  - Suspicious MSHTA Activity
  - Living Off The Land
  asset_type: Endpoint
  cis20:
  - CIS 8
  confidence: 100
  context:
  - Source:Endpoint
  - Stage:Defense Evasion
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1218.005/atomic_red_team/windows-sysmon.log
  impact: 80
  kill_chain_phases:
  - Exploitation
  message: The following $process_name$ has been identified as renamed, spawning from
    $parent_process_name$.
  mitre_attack_id:
  - T1218
  - T1218.005
  nist:
  - PR.PT
  - DE.CM
  observable:
  - name: user
    type: User
    role:
    - Victim
  - name: Computer
    type: Hostname
    role:
    - Victim
  - name: parent_process_name
    type: Process
    role:
    - Parent Process
  - name: process_name
    type: Process
    role:
    - Child Process
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Processes.dest
  - Processes.user
  - Processes.parent_process_name
  - Processes.parent_process
  - Processes.original_file_name
  - Processes.process_name
  - Processes.process
  - Processes.process_id
  - Processes.parent_process_path
  - Processes.process_path
  - Processes.parent_process_id
  risk_score: 80
  security_domain: endpoint