Suspicious Plink Port Forwarding — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2021-01-19 / 2022-10-09.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 2870dc6a4e656e13a9fc7a64223266facdb8f08a40827aeeba9d14c0c84b2292

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: Suspicious Plink Port Forwarding
id: 48a61b29-389f-4032-b317-b30de6b95314
status: test
description: Detects suspicious Plink tunnel port forwarding to a local port
references:
    - https://www.real-sec.com/2019/04/bypassing-network-restrictions-through-rdp-tunneling/
    - https://medium.com/@informationsecurity/remote-ssh-tunneling-with-plink-exe-7831072b3d7d
author: Florian Roth (Nextron Systems)
date: 2021-01-19
modified: 2022-10-09
tags:
    - attack.command-and-control
    - attack.t1572
    - attack.lateral-movement
    - attack.t1021.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Description: 'Command-line SSH, Telnet, and Rlogin client'
        CommandLine|contains: ' -R '
    condition: selection
falsepositives:
    - Administrative activity using a remote port forwarding to a local port
level: high

Original YAML and metadata in JSON

False positives

• Administrative activity using a remote port forwarding to a local port

Source references

• https://www.real-sec.com/2019/04/bypassing-network-restrictions-through-rdp-tunneling/
• https://medium.com/@informationsecurity/remote-ssh-tunneling-with-plink-exe-7831072b3d7d