OpenSSH Server (sshd) Listening on SSH Socket on Windows

Flags OpenSSH (sshd) events showing the SSH server has started listening on a socket.

FreeReviewedSigma · Medium · v2
Product
windows
Service
openssh
Author
mdecrevoisier (SigmaHQ), DRL 1.1
Published
2022-10-25
Updated
2026-07-31
title: OpenSSH Server (sshd) Listening on SSH Socket on Windows
id: 64962fc4-549a-498f-b41f-f08deac7897a
status: test
description: This rule identifies when the OpenSSH server process (sshd) emits an event indicating it has begun listening on an SSH socket. Attackers may enable or start an SSH service to establish remote access, so the listener state is a key indicator of new network-facing exposure. Detection relies on Windows OpenSSH service telemetry with Event ID 4 and an ssld log payload that starts with the exact listening message.
references:
  - https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0008-Lateral%20Movement/T1021.004-Remote%20Service%20SSH
  - https://winaero.com/enable-openssh-server-windows-10/
  - https://learn.microsoft.com/en-us/windows-server/administration/openssh/openssh_install_firstuse
  - https://virtualizationreview.com/articles/2020/05/21/ssh-server-on-windows-10.aspx
  - https://medium.com/threatpunter/detecting-adversary-tradecraft-with-image-load-event-logging-and-eql-8de93338c16
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/openssh/win_sshd_openssh_server_listening_on_socket.yml
author: mdecrevoisier, Huntrule Team
date: 2022-10-25
tags:
  - attack.lateral-movement
  - attack.t1021.004
logsource:
  product: windows
  service: openssh
detection:
  selection:
    EventID: 4
    process: sshd
    payload|startswith: "Server listening on "
  condition: selection
falsepositives:
  - Legitimate administrator activity
level: medium
license: DRL-1.1
related:
  - id: 3ce8e9a4-bc61-4c9b-8e69-d7e2492a8781
    type: derived