Detection rules › Sigma

Operator Bloopers Cobalt Strike Modules

Status
test
Severity
high
Log source
product windows, category process_creation
Author
_pete_0, TheDFIRReport
Source
github.com/SigmaHQ/sigma

Detects Cobalt Strike module/commands accidentally entered in CMD shell

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

title: Operator Bloopers Cobalt Strike Modules
id: 4f154fb6-27d1-4813-a759-78b93e0b9c48
related:
    - id: 647c7b9e-d784-4fda-b9a0-45c565a7b729
      type: similar
status: test
description: Detects Cobalt Strike module/commands accidentally entered in CMD shell
references:
    - https://hstechdocs.helpsystems.com/manuals/cobaltstrike/current/userguide/content/cobalt-4-5-user-guide.pdf
    - https://thedfirreport.com/2021/10/04/bazarloader-and-the-conti-leaks/
    - https://thedfirreport.com/2022/06/16/sans-ransomware-summit-2022-can-you-detect-this/
author: _pete_0, TheDFIRReport
date: 2022-05-06
modified: 2023-01-30
tags:
    - attack.execution
    - attack.t1059.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - OriginalFileName: 'Cmd.Exe'
        - Image|endswith: '\cmd.exe'
    selection_cli:
        CommandLine|contains:
            - 'Invoke-UserHunter'
            - 'Invoke-ShareFinder'
            - 'Invoke-Kerberoast'
            - 'Invoke-SMBAutoBrute'
            - 'Invoke-Nightmare'
            - 'zerologon'
            - 'av_query'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - OriginalFileName: 'Cmd.Exe'
    - Image|endswith: '\cmd.exe'

Stage 2: selection_cli

selection_cli:
    CommandLine|contains:
        - 'Invoke-UserHunter'
        - 'Invoke-ShareFinder'
        - 'Invoke-Kerberoast'
        - 'Invoke-SMBAutoBrute'
        - 'Invoke-Nightmare'
        - 'zerologon'
        - 'av_query'

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
CommandLinematch
  • Invoke-Kerberoast corpus 2 (sigma 2)
  • Invoke-Nightmare corpus 2 (sigma 2)
  • Invoke-SMBAutoBrute
  • Invoke-ShareFinder corpus 2 (sigma 2)
  • Invoke-UserHunter corpus 2 (sigma 2)
  • av_query
  • zerologon
Imageends_with
  • \cmd.exe corpus 130 (sigma 130)
OriginalFileNameeq
  • Cmd.Exe corpus 65 (sigma 43, splunk 17, elastic 5)