Suspicious Get-Variable.exe Creation

testhigh
log source: windows · file_eventauthor frack113date 2022-04-23
01

description

What this is, in brief.

Get-Variable is a valid PowerShell cmdlet WindowsApps is by default in the path where PowerShell is executed. So when the Get-Variable command is issued on PowerShell execution, the system first looks for the Get-Variable executable in the path and executes the malicious binary instead of looking for the PowerShell cmdlet.

02

tags

attack.privilege-escalationattack.persistenceattack.stealthattack.t1546attack.t1027
03

rule source (YAML)

title: Suspicious Get-Variable.exe Creation
id: 0c3fac91-5627-46e8-a6a8-a0d7b9b8ae1b
status: test
description: |
    Get-Variable is a valid PowerShell cmdlet
    WindowsApps is by default in the path where PowerShell is executed.
    So when the Get-Variable command is issued on PowerShell execution, the system first looks for the Get-Variable executable in the path and executes the malicious binary instead of looking for the PowerShell cmdlet.
references:
    - https://blog.malwarebytes.com/threat-intelligence/2022/04/colibri-loader-combines-task-scheduler-and-powershell-in-clever-persistence-technique/
    - https://www.joesandbox.com/analysis/465533/0/html
author: frack113
date: 2022-04-23
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.stealth
    - attack.t1546
    - attack.t1027
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith: 'Local\Microsoft\WindowsApps\Get-Variable.exe'
    condition: selection
falsepositives:
    - Unknown
level: high
04

detects techniques (2)

ATT&CK techniques this enables or maps to.

05

references

External citations — patches, advisories, analysis.