Detection rules › Sigma

SMB Spoolss Name Piped Usage

Status
test
Severity
medium
Log source
product zeek, service smb_files
Author
OTR (Open Threat Research), @neu5ron
Source
github.com/SigmaHQ/sigma

Detects the use of the spoolss named pipe over SMB. This can be used to trigger the authentication via NTLM of any machine that has the spoolservice enabled.

MITRE ATT&CK coverage

Rule body yaml

title: SMB Spoolss Name Piped Usage
id: bae2865c-5565-470d-b505-9496c87d0c30
status: test
description: Detects the use of the spoolss named pipe over SMB. This can be used to trigger the authentication via NTLM of any machine that has the spoolservice enabled.
references:
    - https://posts.specterops.io/hunting-in-active-directory-unconstrained-delegation-forests-trusts-71f2b33688e1
    - https://dirkjanm.io/a-different-way-of-abusing-zerologon/
    - https://twitter.com/_dirkjan/status/1309214379003588608
author: OTR (Open Threat Research), @neu5ron
date: 2018-11-28
modified: 2022-10-09
tags:
    - attack.lateral-movement
    - attack.t1021.002
logsource:
    product: zeek
    service: smb_files
detection:
    selection:
        path|endswith: 'IPC$'
        name: spoolss
    condition: selection
falsepositives:
    - Domain Controllers that are sometimes, commonly although should not be, acting as printer servers too
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    path|endswith: 'IPC$'
    name: spoolss

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
nameeq
  • spoolss
pathends_with
  • IPC$