Detection rules › Sigma

Suspicious Velociraptor Child Process

Status
experimental
Severity
high
Log source
product windows, category process_creation
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the suspicious use of the Velociraptor DFIR tool to execute other tools or download additional payloads, as seen in a campaign where it was abused for remote access and to stage further attacks.

MITRE ATT&CK coverage

TacticTechniques
Command & ControlT1219 Remote Access Tools

Event coverage

Rule body yaml

title: Suspicious Velociraptor Child Process
id: 4bc90587-e6ca-4b41-be0b-ed4d04e4ed0c
status: experimental
description: Detects the suspicious use of the Velociraptor DFIR tool to execute other tools or download additional payloads, as seen in a campaign where it was abused for remote access and to stage further attacks.
references:
    - https://news.sophos.com/en-us/2025/08/26/velociraptor-incident-response-tool-abused-for-remote-access/
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-08-29
tags:
    - attack.command-and-control
    - attack.persistence
    - attack.t1219
logsource:
    category: process_creation
    product: windows
detection:
    selection_parent:
        ParentImage|endswith: '\Velociraptor.exe'
    selection_child_vscode_tunnel:
        CommandLine|contains|all:
            - 'code.exe'
            - 'tunnel'
            - '--accept-server-license-terms'
    selection_child_msiexec:
        CommandLine|contains|all:
            - 'msiexec'
            - '/i'
            - 'http'
    selection_child_powershell:
        Image|endswith:
            - '\powershell.exe'
            - '\powershell_ise.exe'
            - '\pwsh.exe'
        CommandLine|contains:
            - 'Invoke-WebRequest '
            - 'IWR '
            - '.DownloadFile'
            - '.DownloadString'
    # Add more child process patterns as needed
    condition: selection_parent and 1 of selection_child_*
falsepositives:
    - Legitimate administrators or incident responders might use Velociraptor to execute scripts or tools. However, the combination of Velociraptor spawning these specific processes with these command lines is suspicious. Tuning may be required to exclude known administrative actions or specific scripts.
level: high

Stages and Predicates

Stage 0: condition

selection_parent and 1 of selection_child_*

Stage 1: selection_parent

selection_parent:
    ParentImage|endswith: '\Velociraptor.exe'

Stage 2: selection_child_vscode_tunnel

selection_child_vscode_tunnel:
    CommandLine|contains|all:
        - 'code.exe'
        - 'tunnel'
        - '--accept-server-license-terms'

Stage 3: selection_child_msiexec

selection_child_msiexec:
    CommandLine|contains|all:
        - 'msiexec'
        - '/i'
        - 'http'

Stage 4: selection_child_powershell

selection_child_powershell:
    Image|endswith:
        - '\powershell.exe'
        - '\powershell_ise.exe'
        - '\pwsh.exe'
    CommandLine|contains:
        - 'Invoke-WebRequest '
        - 'IWR '
        - '.DownloadFile'
        - '.DownloadString'

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
  • --accept-server-license-terms corpus 4 (sigma 3, splunk 1)
  • .DownloadFile corpus 3 (sigma 2, chronicle 1)
  • .DownloadString corpus 2 (sigma 2)
  • /i corpus 3 (sigma 2, splunk 1)
  • IWR corpus 13 (sigma 11, chronicle 2)
  • Invoke-WebRequest corpus 5 (sigma 4, chronicle 1)
  • code.exe
  • http corpus 39 (sigma 34, elastic 2, chronicle 2, splunk 1)
  • msiexec corpus 5 (sigma 5)
  • tunnel corpus 5 (sigma 3, elastic 1, splunk 1)
Imageends_with
  • \powershell.exe corpus 182 (sigma 182)
  • \powershell_ise.exe corpus 41 (sigma 41)
  • \pwsh.exe corpus 168 (sigma 168)
ParentImageends_with
  • \Velociraptor.exe