Detection rules › Sigma

Powershell Executed From Headless ConHost Process

Severity
medium
Author
Matt Anderson (Huntress)
Source
upstream

Detects the use of powershell commands from headless ConHost window. The "--headless" flag hides the windows from the user upon execution.

MITRE ATT&CK coverage

TacticTechniques
ExecutionT1059.001 Command and Scripting Interpreter: PowerShell, T1059.003 Command and Scripting Interpreter: Windows Command Shell
Defense EvasionT1564.003 Hide Artifacts: Hidden Window

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation

Stages and Predicates

Stage 1: all of selection_img

or:
Image|endswith: '\conhost.exe'
OriginalFileName: CONHOST.EXE

Stage 2: all of selection_cli

CommandLine|contains: --headless
CommandLine|contains: powershell

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
CommandLinematch
  • --headless corpus 5 (sigma 5)
  • powershell corpus 16 (sigma 16)
Imageends_with
  • \conhost.exe corpus 7 (sigma 7)
OriginalFileNameeq
  • CONHOST.EXE corpus 3 (sigma 3)