Use Icacls to Hide File to Everyone

Detect use of icacls to deny access for everyone in Users folder sometimes used to hide malicious files

Detection logic

selection_icacls

- OriginalFileName: iCACLS.EXE
- Image|endswith: \icacls.exe

selection_cmd

CommandLine|contains|all:
  - /deny
  - "*S-1-1-0:"

Condition

all of selection_*

Raw YAML

title: Use Icacls to Hide File to Everyone
id: 4ae81040-fc1c-4249-bfa3-938d260214d9
status: test
description: Detect use of icacls to deny access for everyone in Users folder sometimes used to hide malicious files
references:
    - https://app.any.run/tasks/1df999e6-1cb8-45e3-8b61-499d1b7d5a9b/
author: frack113
date: 2022-07-18
modified: 2024-04-29
tags:
    - attack.stealth
    - attack.t1564.001
logsource:
    category: process_creation
    product: windows
detection:
    selection_icacls:
        - OriginalFileName: 'iCACLS.EXE'
        - Image|endswith: '\icacls.exe'
    selection_cmd: # icacls "C:\Users\admin\AppData\Local\37f92fe8-bcf0-4ee0-b8ba-561f797f5696" /deny *S-1-1-0:(OI)(CI)(DE,DC)
        CommandLine|contains|all:
            - '/deny'
            - '*S-1-1-0:'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

False positives

Unknown

References

https://app.any.run/tasks/1df999e6-1cb8-45e3-8b61-499d1b7d5a9b/

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