Suspicious Copy From or To System Directory (via process_creation)

title: Suspicious Copy From or To System Directory (via process_creation)
id: 469bf522-81bf-5b88-be42-bffa8b27f13d
status: stable
description: This rule detects an anomalous copy operation that tries to copy a program from system (System32, SysWOW64, WinSxS) directories to another on disk. Often used to move LOLBINs such as 'certutil' or 'desktopimgdownldr' to a different location with a different name to bypass detections based on locations.
references:
    - https://attack.mitre.org/techniques/T1036/003/
    - https://www.hybrid-analysis.com/sample/8da5b75b6380a41eee3a399c43dfe0d99eeefaa1fd21027a07b1ecaa4cd96fdd?environmentId=120
    - https://web.archive.org/web/20180331144337/https://www.fireeye.com/blog/threat-research/2018/03/sanny-malware-delivery-method-updated-in-recently-observed-attacks.html
    - https://thedfirreport.com/2023/08/28/html-smuggling-leads-to-domain-wide-ransomware/
author: Huntrule Team
date: 2026-05-31
tags:
    - attack.stealth
    - attack.t1036.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_img_cmd:
        Image|endswith: '\cmd.exe'
        CommandLine|contains: 'copy '
    selection_img_pwsh:
        Image|endswith:
            - '\powershell.exe'
            - '\pwsh.exe'
        CommandLine|contains:
            - 'copy-item'
            - ' copy '
            - 'cpi '
            - ' cp '
    selection_img_other:
        - Image|endswith:
              - '\robocopy.exe'
              - '\xcopy.exe'
        - OriginalFileName:
              - 'robocopy.exe'
              - 'XCOPY.EXE'
    selection_target:
        CommandLine|re|i: \s['"]?C:\\Windows\\(?:System32|SysWOW64|WinSxS)
    filter_optional_avira:
        Image|endswith: '\cmd.exe'
        CommandLine|contains|all:
            - '/c copy'
            - '\Temp\'
            - '\avira_system_speedup.exe'
        CommandLine|contains:
            - 'C:\Program Files\Avira\'
            - 'C:\Program Files (x86)\Avira\'
    condition: 1 of selection_img_* and selection_target and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium