Default RDP Port Changed to Non Standard Port — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: high. Source dates: 2022-01-01 / 2024-03-25.

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

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 8fd6641680a3a22f1bf2bb0daaa0b7ea2e836aa322006a998a4240dc68cdcaab

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: Default RDP Port Changed to Non Standard Port
id: 509e84b9-a71a-40e0-834f-05470369bd1e
status: test
description: |
    Detects changes to the default RDP port.
    Remote desktop is a common feature in operating systems. It allows a user to log into a remote system using an interactive session with a graphical user interface.
    Microsoft refers to its implementation of the Remote Desktop Protocol (RDP) as Remote Desktop Services (RDS).
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1021.001/T1021.001.md
author: frack113
date: 2022-01-01
modified: 2024-03-25
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1547.010
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|endswith: '\Control\Terminal Server\WinStations\RDP-Tcp\PortNumber'
    filter_main_port:
        Details: DWORD (0x00000d3d) # 3389
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules/windows/registry/registry_set/registry_set_change_rdp_port/info.yml
simulation:
    - type: atomic-red-team
      name: Changing RDP Port to Non Standard Port via Powershell
      technique: T1021.001
      atomic_guid: 2f840dd4-8a2e-4f44-beb3-6b2399ea3771
    - type: atomic-red-team
      name: Changing RDP Port to Non Standard Port via Command_Prompt
      technique: T1021.001
      atomic_guid: 74ace21e-a31c-4f7d-b540-53e4eb6d1f73

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1021.001/T1021.001.md