Enumerate All Information With Whoami.EXE

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

Detects the execution of "whoami.exe" with the "/all" flag

MITRE ATT&CK coverage

Tactic	Techniques
Discovery	`T1033` System Owner/User Discovery

Telemetry coverage

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

Rule body

title: Enumerate All Information With Whoami.EXE
id: c248c896-e412-4279-8c15-1c558067b6fa
status: test
description: Detects the execution of "whoami.exe" with the "/all" flag
references:
    - https://brica.de/alerts/alert/public/1247926/agent-tesla-keylogger-delivered-inside-a-power-iso-daa-archive/
    - https://app.any.run/tasks/7eaba74e-c1ea-400f-9c17-5e30eee89906/
    - https://www.youtube.com/watch?v=DsJ9ByX84o4&t=6s
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
date: 2023-12-04
modified: 2024-03-05
tags:
    - attack.discovery
    - attack.t1033
    - car.2016-03-001
logsource:
    category: process_creation
    product: windows
detection:
    selection_main_img:
        - Image|endswith: '\whoami.exe'
        - OriginalFileName: 'whoami.exe'
    selection_main_cli:
        CommandLine|contains|windash: ' -all'
    condition: all of selection_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: `condition`

all of selection_main_*

Stage 1: `selection_main_img`

selection_main_img:
    - Image|endswith: '\whoami.exe'
    - OriginalFileName: 'whoami.exe'

Stage 2: `selection_main_cli`

selection_main_cli:
    CommandLine|contains|windash: ' -all'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`-all` transforms: `windash` corpus 2 (sigma 2)	`field:"CommandLine" kind:match value:" -all"`
`Image`	ends_with	`\whoami.exe` corpus 19 (sigma 19)	`field:"Image" kind:ends_with value:"\whoami.exe"`
`OriginalFileName`	eq	`whoami.exe` corpus 9 (sigma 9)	`field:"OriginalFileName" kind:eq value:"whoami.exe"`

Enumerate All Information With Whoami.EXE

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_main_img

Stage 2: selection_main_cli

Indicators

Stage 0: `condition`

Stage 1: `selection_main_img`

Stage 2: `selection_main_cli`