PowerShell Script Block: SMB QUIC Share Mapping via New-SmbMapping

Alerts when PowerShell maps Windows SMB shares using New-SmbMapping with -TransportType QUIC.

FreeReviewedSigma · Medium · v5
Product
windows
Category
ps_script
Author
frack113 (SigmaHQ), DRL 1.1
Published
2023-07-21
Updated
2026-07-31
title: "PowerShell Script Block: SMB QUIC Share Mapping via New-SmbMapping"
id: 9a23f44c-316a-4ca7-876e-57cdd4b4e1a4
related:
  - id: 2238d337-42fb-4971-9a68-63570f2aede4
    type: similar
  - id: 6df07c3b-8456-4f8b-87bb-fe31ec964cae
    type: derived
status: test
description: This rule flags PowerShell script content that includes New-SmbMapping combined with the -TransportType QUIC parameter, indicating Windows SMB share mapping over QUIC. Unexpected SMB-over-QUIC usage can be leveraged for stealthy lateral movement or unusual remote access patterns. It relies on PowerShell Script Block Logging telemetry capturing the script block text containing both required strings.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/74438b0237d141ee9c99747976447dc884cb1a39/atomics/T1570/T1570.md
  - https://learn.microsoft.com/en-us/powershell/module/smbshare/new-smbmapping?view=windowsserver2022-ps
  - https://www.trustedsec.com/blog/making-smb-accessible-with-ntlmquic/
  - https://github.com/SigmaHQ/sigma/blob/master/rules-threat-hunting/windows/powershell/powershell_script/posh_ps_new_smbmapping_quic.yml
author: frack113, Huntrule Team
date: 2023-07-21
tags:
  - attack.lateral-movement
  - attack.t1570
  - detection.threat-hunting
logsource:
  product: windows
  category: ps_script
  definition: "Requirements: Script Block Logging must be enabled"
detection:
  selection:
    ScriptBlockText|contains|all:
      - New-SmbMapping
      - -TransportType QUIC
  condition: selection
falsepositives:
  - Due to the nature of the script block, the matching of the string could sometimes result in a false positive. Use this rule to hunt for potential malicious or suspicious scripts.
level: medium
license: DRL-1.1