SQL Client Tools PowerShell Session Detection

Status: test
Severity: medium
Log source: category process_creation, product windows
Author: Agro (@agro_sev) oscd.communitly
Source: github.com/SigmaHQ/sigma

This rule detects execution of a PowerShell code through the sqltoolsps.exe utility, which is included in the standard set of utilities supplied with the Microsoft SQL Server Management studio. Script blocks are not logged in this case, so this utility helps to bypass protection mechanisms based on the analysis of these logs.

Known false positives

Direct PS command execution through SQLToolsPS.exe is uncommon, childprocess sqltoolsps.exe spawned by smss.exe is a legitimate action.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059.001` Command and Scripting Interpreter: PowerShell `T1127` Trusted Developer Utilities Proxy Execution
Stealth	`T1127` Trusted Developer Utilities Proxy Execution

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation

Rule body

title: SQL Client Tools PowerShell Session Detection
id: a746c9b8-a2fb-4ee5-a428-92bee9e99060
status: test
description: |
  This rule detects execution of a PowerShell code through the sqltoolsps.exe utility, which is included in the standard set of utilities supplied with the Microsoft SQL Server Management studio.
  Script blocks are not logged in this case, so this utility helps to bypass protection mechanisms based on the analysis of these logs.
references:
    - https://github.com/LOLBAS-Project/LOLBAS/blob/8283d8d91552213ded165fd36deb6cb9534cb443/yml/OtherMSBinaries/Sqltoolsps.yml
    - https://twitter.com/pabraeken/status/993298228840992768
author: 'Agro (@agro_sev) oscd.communitly'
date: 2020-10-13
modified: 2022-02-25
tags:
    - attack.execution
    - attack.stealth
    - attack.t1059.001
    - attack.t1127
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith: '\sqltoolsps.exe'
        - ParentImage|endswith: '\sqltoolsps.exe'
        - OriginalFileName: '\sqltoolsps.exe'
    filter:
        ParentImage|endswith: '\smss.exe'
    condition: selection and not filter
falsepositives:
    - Direct PS command execution through SQLToolsPS.exe is uncommon, childprocess sqltoolsps.exe spawned by smss.exe is a legitimate action.
level: medium

Stages and Predicates

Stage 0: `condition`

selection and not filter

Stage 1: `selection`

selection:
    - Image|endswith: '\sqltoolsps.exe'
    - ParentImage|endswith: '\sqltoolsps.exe'
    - OriginalFileName: '\sqltoolsps.exe'

Stage 2: `not filter`

filter:
    ParentImage|endswith: '\smss.exe'

Exclusions

The rule actively suppresses these predicates.

Field	Kind	Excluded values	Search
`ParentImage`	ends_with	`\smss.exe`	`excludes:ParentImage` `field:"ParentImage" value:"\smss.exe"`

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`Image`	ends_with	`\sqltoolsps.exe`	`field:"Image" kind:ends_with value:"\sqltoolsps.exe"`
`OriginalFileName`	eq	`\sqltoolsps.exe`	`field:"OriginalFileName" kind:eq value:"\sqltoolsps.exe"`
`ParentImage`	ends_with	`\sqltoolsps.exe`	`field:"ParentImage" kind:ends_with value:"\sqltoolsps.exe"`