Detection rules › Sigma

PUA - AdvancedRun Suspicious Execution

Status
test
Severity
high
Log source
product windows, category process_creation
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the execution of AdvancedRun utility in the context of the TrustedInstaller, SYSTEM, Local Service or Network Service accounts

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: PUA - AdvancedRun Suspicious Execution
id: fa00b701-44c6-4679-994d-5a18afa8a707
related:
    - id: d2b749ee-4225-417e-b20e-a8d2193cbb84
      type: similar
status: test
description: Detects the execution of AdvancedRun utility in the context of the TrustedInstaller, SYSTEM, Local Service or Network Service accounts
references:
    - https://twitter.com/splinter_code/status/1483815103279603714
    - https://medium.com/s2wblog/analysis-of-destructive-malware-whispergate-targeting-ukraine-9d5d158f19f3
    - https://www.elastic.co/security-labs/operation-bleeding-bear
    - https://www.winhelponline.com/blog/run-program-as-system-localsystem-account-windows/
author: Florian Roth (Nextron Systems)
date: 2022-01-20
modified: 2023-02-21
tags:
    - attack.privilege-escalation
    - attack.stealth
    - attack.t1134.002
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        CommandLine|contains:
            - '/EXEFilename'
            - '/CommandLine'
    selection_runas:
        - CommandLine|contains:
              - ' /RunAs 8 '
              - ' /RunAs 4 '
              - ' /RunAs 10 '
              - ' /RunAs 11 '
        - CommandLine|endswith:
              - '/RunAs 8'
              - '/RunAs 4'
              - '/RunAs 10'
              - '/RunAs 11'
    condition: all of selection*
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_pua_advancedrun_priv_user/info.yml

Stages and Predicates

Stage 0: condition

all of selection*

Stage 1: selection

selection:
    CommandLine|contains:
        - '/EXEFilename'
        - '/CommandLine'

Stage 2: selection_runas

selection_runas:
    - CommandLine|contains:
          - ' /RunAs 8 '
          - ' /RunAs 4 '
          - ' /RunAs 10 '
          - ' /RunAs 11 '
    - CommandLine|endswith:
          - '/RunAs 8'
          - '/RunAs 4'
          - '/RunAs 10'
          - '/RunAs 11'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLineends_with
  • /RunAs 10
  • /RunAs 11
  • /RunAs 4
  • /RunAs 8
CommandLinematch
  • /RunAs 10
  • /RunAs 11
  • /RunAs 4
  • /RunAs 8
  • /CommandLine
  • /EXEFilename