CAR-2014-02-001.yaml

---
title: Service Binary Modifications
submission_date: 2014/02/14
information_domain: Host
platforms:
  - Windows
subtypes:
  - Registry File Process
analytic_types:
  - Situational Awareness
  - TTP
contributors:
  - MITRE
id: CAR-2014-02-001
description: |
  Adversaries may modify the binary file for an existing service to achieve [Persistence](https://attack.mitre.org/tactics/TA0003) while potentially [evading defenses](https://attack.mitre.org/tactics/TA0005). If a newly created or modified runs as a service, it may indicate APT activity. However, services are frequently installed by legitimate software. A well-tuned baseline is essential to differentiating between benign and malicious service modifications.

  ### Output Description

  The Service Name and approximate time in which changes occurred on each host
coverage:
  - technique: T1543
    tactics:
      - TA0003
      - TA0004
    subtechniques:
      - T1543.003
    coverage: Moderate
  - technique: T1574
    tactics:
      - TA0003
      - TA0004
    subtechniques:
      - T1574.010
    coverage: Moderate
  - technique: T1569
    tactics:
      - TA0002
    subtechniques:
      - T1569.002
    coverage: Moderate
implementations:
  - description: 'Look for events where a file was created and then later run as a service. In these cases, a new service has been created or the binary has been modified. Many programs, such as `msiexec.exe`, do these behaviors legitimately and can be used to help validate legitimate service creations/modifications.'
    code: |
      legitimate_installers = ["C:\windows\system32\msiexec.exe", "C:\windows\syswow64\msiexec.exe", ...]

      file_change = search File:Create,Modify
      process = search Process:Create
      service_process = filter processes where (parent_exe == "services.exe")
      modified_service = join (search, filter) where (
       file_change.time < service_process.time and
       file_change.file_path == service_process.image_path
      )

      modified_service = filter modified_service where (modified_service.file_change.image_path not in legitimate_installers)
      output modified_service
    type: pseudocode
data_model_references:
  - file/create/file_path
  - file/create/image_path
  - process/create/image_path
  - process/create/parent_exe
d3fend_mappings:
  - iri: d3f:ServiceBinaryVerification
    id: D3-SBV
    label: Service Binary Verification