LOL-Binary Copied From System Directory

01

description

What this is, in brief.

Detects a suspicious copy operation that tries to copy a known LOLBIN from system (System32, SysWOW64, WinSxS) directories to another on disk in order to bypass detections based on locations.

02

rule source (YAML)

title: LOL-Binary Copied From System Directory
id: f5d19838-41b5-476c-98d8-ba8af4929ee2
related:
    - id: fff9d2b7-e11c-4a69-93d3-40ef66189767
      type: derived
status: test
description: |
    Detects a suspicious copy operation that tries to copy a known LOLBIN from system (System32, SysWOW64, WinSxS) directories to another on disk in order to bypass detections based on locations.
references:
    - 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/
    - https://www.virustotal.com/gui/file/14e722855605ba78dc1d21153f0e1be90e7528149f2cd2d7d6eba8ef27534bdc/behavior
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-08-29
modified: 2025-11-27
tags:
    - attack.stealth
    - attack.t1036.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_tools_cmd:
        Image|endswith: '\cmd.exe'
        CommandLine|contains: 'copy '
    selection_tools_pwsh:
        Image|endswith:
            - '\powershell.exe'
            - '\pwsh.exe'
        CommandLine|contains:
            - 'copy-item'
            - ' copy '
            - 'cpi '
            - ' cp '
    selection_tools_other:
        - Image|endswith:
              - '\robocopy.exe'
              - '\xcopy.exe'
        - OriginalFileName:
              - 'robocopy.exe'
              - 'XCOPY.EXE'
    selection_target_path:
        CommandLine|contains:
            - '\System32'
            - '\SysWOW64'
            - '\WinSxS'
    selection_target_lolbin:
        CommandLine|contains:
            # Note: add more binaries to increase coverage
            - '\bitsadmin.exe'
            - '\calc.exe'
            - '\certutil.exe'
            - '\cmdl32.exe'
            - '\cscript.exe'
            - '\mshta.exe'
            - '\rundll32.exe'
            - '\wscript.exe'
            - '\ie4uinit.exe'
    condition: 1 of selection_tools_* and all of selection_target_*
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_susp_copy_system_dir_lolbin/info.yml

04

detects techniques (1)

ATT&CK techniques this enables or maps to.

T1036.003Rename Legitimate Utilities

05

references

External citations — patches, advisories, analysis.