Suspect Svchost Activity — Sigma Rule

Rule metadata and linked tags

Author: David Burkett, @signalblur. Source status: test; severity: high. Source dates: 2019-12-28 / 2022-06-27.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: ef11ccdb615222468d53b68b9f8b27ce3638e4704ac95c099747967565d04fa9

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Suspect Svchost Activity
id: 16c37b52-b141-42a5-a3ea-bbe098444397
status: test
description: It is extremely abnormal for svchost.exe to spawn without any CLI arguments and is normally observed when a malicious process spawns the process and injects code into the process memory space.
references:
    - https://web.archive.org/web/20180718061628/https://securitybytes.io/blue-team-fundamentals-part-two-windows-processes-759fe15965e2
author: David Burkett, @signalblur
date: 2019-12-28
modified: 2022-06-27
tags:
    - attack.privilege-escalation
    - attack.stealth
    - attack.t1055
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|endswith: 'svchost.exe'
        Image|endswith: '\svchost.exe'
    filter:
        - ParentImage|endswith:
              - '\rpcnet.exe'
              - '\rpcnetp.exe'
        - CommandLine: null  # no CommandLine value available
    condition: selection and not filter
falsepositives:
    - Rpcnet.exe / rpcnetp.exe which is a lojack style software. https://www.blackhat.com/docs/us-14/materials/us-14-Kamlyuk-Kamluk-Computrace-Backdoor-Revisited.pdf
level: high

Original YAML and metadata in JSON

False positives

• Rpcnet.exe / rpcnetp.exe which is a lojack style software. https://www.blackhat.com/docs/us-14/materials/us-14-Kamlyuk-Kamluk-Computrace-Backdoor-Revisited.pdf

Source references

• https://web.archive.org/web/20180718061628/https://securitybytes.io/blue-team-fundamentals-part-two-windows-processes-759fe15965e2