Password Provided In Command Line Of Net.EXE

Status: test
Severity: medium
Log source: category process_creation, product windows
Author: Tim Shelton (HAWK.IO)
Source: github.com/SigmaHQ/sigma

Detects a when net.exe is called with a password in the command line

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1078` Valid Accounts
Persistence	`T1078` Valid Accounts
Privilege Escalation	`T1078` Valid Accounts
Stealth	`T1078` Valid Accounts
Lateral Movement	`T1021.002` Remote Services: SMB/Windows Admin Shares

Telemetry coverage

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

Rule body

title: Password Provided In Command Line Of Net.EXE
id: d4498716-1d52-438f-8084-4a603157d131
status: test
description: Detects a when net.exe is called with a password in the command line
references:
    - Internal Research
author: Tim Shelton (HAWK.IO)
date: 2021-12-09
modified: 2023-02-21
tags:
    - attack.initial-access
    - attack.persistence
    - attack.privilege-escalation
    - attack.lateral-movement
    - attack.stealth
    - attack.t1021.002
    - attack.t1078
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\net.exe'
              - '\net1.exe'
        - OriginalFileName:
              - 'net.exe'
              - 'net1.exe'
    selection_cli:
        CommandLine|contains|all:
            - ' use '
            - ':*\\'
            - '/USER:* *'
    filter_main_empty:
        CommandLine|endswith: ' '
    condition: all of selection_* and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: `condition`

all of selection_* and not 1 of filter_main_*

Stage 1: `selection_img`

selection_img:
    - Image|endswith:
          - '\net.exe'
          - '\net1.exe'
    - OriginalFileName:
          - 'net.exe'
          - 'net1.exe'

Stage 2: `selection_cli`

selection_cli:
    CommandLine|contains|all:
        - ' use '
        - ':*\\'
        - '/USER:* *'

Stage 3: `not filter_main_empty`

filter_main_empty:
    CommandLine|endswith: ' '

Exclusions

The rule actively suppresses these predicates.

Field	Kind	Excluded values	Search
`CommandLine`	ends_with		`excludes:CommandLine` `field:"CommandLine" value:" "`

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`use` corpus 6 (sigma 6) `/USER:* ` `:\\`	`field:"CommandLine" kind:match`
`Image`	ends_with	`\net.exe` corpus 49 (sigma 49) `\net1.exe` corpus 47 (sigma 47)	`field:"Image" kind:ends_with`
`OriginalFileName`	eq	`net.exe` corpus 31 (sigma 19, elastic 10, splunk 2) `net1.exe` corpus 44 (sigma 19, splunk 19, elastic 6)	`field:"OriginalFileName" kind:eq`

Password Provided In Command Line Of Net.EXE

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_img

Stage 2: selection_cli

Stage 3: not filter_main_empty

Exclusions

Indicators

Stage 0: `condition`

Stage 1: `selection_img`

Stage 2: `selection_cli`

Stage 3: `not filter_main_empty`