Detection rules › Sigma

PUA - RunXCmd Execution

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

Detects the use of the RunXCmd tool to execute commands with System or TrustedInstaller accounts

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: PUA - RunXCmd Execution
id: 93199800-b52a-4dec-b762-75212c196542
status: test
description: Detects the use of the RunXCmd tool to execute commands with System or TrustedInstaller accounts
references:
    - https://www.d7xtech.com/free-software/runx/
    - https://www.winhelponline.com/blog/run-program-as-system-localsystem-account-windows/
author: Florian Roth (Nextron Systems)
date: 2022-01-24
modified: 2023-02-14
tags:
    - attack.execution
    - attack.t1569.002
    - attack.s0029
logsource:
    category: process_creation
    product: windows
detection:
    selection_account:
        CommandLine|contains:
            - ' /account=system '
            - ' /account=ti '
    selection_exec:
        CommandLine|contains: '/exec='
    condition: all of selection_*
falsepositives:
    - Legitimate use by administrators
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_account

selection_account:
    CommandLine|contains:
        - ' /account=system '
        - ' /account=ti '

Stage 2: selection_exec

selection_exec:
    CommandLine|contains: '/exec='

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
  • /account=system
  • /account=ti
  • /exec=