Detection rules › Sigma

Potential PowerShell Obfuscation Via WCHAR/CHAR

Status
test
Severity
high
Log source
product windows, category process_creation
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects suspicious encoded character syntax often used for defense evasion

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: Potential PowerShell Obfuscation Via WCHAR/CHAR
id: e312efd0-35a1-407f-8439-b8d434b438a6
status: test
description: Detects suspicious encoded character syntax often used for defense evasion
references:
    - https://twitter.com/0gtweet/status/1281103918693482496
author: Florian Roth (Nextron Systems)
date: 2020-07-09
modified: 2025-03-03
tags:
    - attack.execution
    - attack.stealth
    - attack.t1059.001
    - attack.t1027
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains:
            - '[char]0x'
            - '(WCHAR)0x'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains:
        - '[char]0x'
        - '(WCHAR)0x'

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
  • (WCHAR)0x
  • [char]0x