Detection rules › Sigma

Potential Lateral Movement via Windows Remote Shell

Status
experimental
Severity
medium
Log source
product windows, category process_creation
Author
Liran Ravich
Source
github.com/SigmaHQ/sigma

Detects a child process spawned by 'winrshost.exe', which suggests remote command execution through Windows Remote Shell (WinRs) and may indicate potential lateral movement activity.

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: Potential Lateral Movement via Windows Remote Shell
id: 79df3f68-dccb-48e9-9171-b75cbc37c51d
status: experimental
description: |
    Detects a child process spawned by 'winrshost.exe', which suggests remote command execution through Windows Remote Shell (WinRs) and may indicate potential lateral movement activity.
references:
    - https://cardinalops.com/blog/living-off-winrm-abusing-complexity-in-remote-management/
    - https://www.ired.team/offensive-security/lateral-movement/winrs-for-lateral-movement
author: Liran Ravich
date: 2025-10-22
tags:
    - attack.lateral-movement
    - attack.t1021.006
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        # Note: Example of command to simulate (winrm needs to be enabled): "c:\Windows\System32\winrs.exe" powershell
        ParentImage|endswith: '\winrshost.exe'
    filter_main_conhost:
        Image: 'C:\Windows\System32\conhost.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Legitimate use of WinRM within the organization
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    ParentImage|endswith: '\winrshost.exe'

Stage 2: not filter_main_conhost

filter_main_conhost:
    Image: 'C:\Windows\System32\conhost.exe'

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
ImageeqC:\Windows\System32\conhost.exe

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
ParentImageends_with
  • \winrshost.exe