Detection rules › Sigma

WhoAmI as Parameter

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

Detects a suspicious process command line that uses whoami as first parameter (as e.g. used by EfsPotato)

MITRE ATT&CK coverage

TacticTechniques
DiscoveryT1033 System Owner/User Discovery

Event coverage

Rule body yaml

title: WhoAmI as Parameter
id: e9142d84-fbe0-401d-ac50-3e519fb00c89
status: test
description: Detects a suspicious process command line that uses whoami as first parameter (as e.g. used by EfsPotato)
references:
    - https://twitter.com/blackarrowsec/status/1463805700602224645?s=12
author: Florian Roth (Nextron Systems)
date: 2021-11-29
modified: 2022-12-25
tags:
    - attack.discovery
    - attack.t1033
    - car.2016-03-001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains: '.exe whoami'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains: '.exe whoami'

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
  • .exe whoami