Sigma rule: System File Execution Location Anomaly

Rule

Title

System File Execution Location Anomaly

Status

test

Level

high

Author

Florian Roth (Nextron Systems), Patrick Bareiss, Anton Kutepov, oscd.community, Nasreddine Bencherchali (Nextron Systems)

Date

2017-11-27

Modified

2026-07-28

File

rules/windows/process_creation/proc_creation_win_susp_system_exe_anomaly.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the execution of a Windows system binary that is usually located in the system folder from an uncommon location.

Log source

product

windows

category

process_creation

Detection

selection:
    Image|endswith:
        - '\atbroker.exe'
        - '\audiodg.exe'
        - '\bcdedit.exe'
        - '\bitsadmin.exe'
        - '\certreq.exe'
        - '\certutil.exe'
        - '\cmstp.exe'
        - '\conhost.exe'
        - '\consent.exe'
        - '\cscript.exe'
        - '\csrss.exe'
        - '\dashost.exe'
        - '\defrag.exe'
        - '\dfrgui.exe' # Was seen used by Lazarus Group - https://asec.ahnlab.com/en/39828/
        - '\dism.exe'
        - '\dllhost.exe'
        - '\dllhst3g.exe'
        - '\dwm.exe'
        - '\eventvwr.exe'
        - '\fsquirt.exe' # was seen used by sidewinder APT - https://securelist.com/sidewinder-apt/114089/
        - '\finger.exe'
        - '\logonui.exe'
        - '\LsaIso.exe'
        - '\lsass.exe'
        - '\lsm.exe'
        - '\msiexec.exe'
        - '\ntoskrnl.exe'
        - '\powershell_ise.exe'
        - '\powershell.exe'
        - '\pwsh.exe'
        - '\regsvr32.exe'
        - '\rundll32.exe'
        - '\runonce.exe'
        - '\RuntimeBroker.exe'
        - '\schtasks.exe'
        - '\services.exe'
        - '\sihost.exe'
        - '\smartscreen.exe'
        - '\smss.exe'
        - '\spoolsv.exe'
        - '\svchost.exe'
        - '\taskhost.exe'
        - '\taskhostw.exe'
        - '\Taskmgr.exe'
        - '\userinit.exe'
        - '\werfault.exe'
        - '\werfaultsecure.exe'
        - '\wininit.exe'
        - '\winlogon.exe'
        - '\winver.exe'
        - '\wlanext.exe'
        - '\wmic.exe'
        - '\wscript.exe'
        - '\wsl.exe'
        - '\wsmprovhost.exe' # Was seen used by Lazarus Group - https://asec.ahnlab.com/en/39828/
filter_main_generic:
    Image|startswith:
        - 'C:\$WINDOWS.~BT\'
        - 'C:\$WinREAgent\'
        - 'C:\Windows\SoftwareDistribution\'
        - 'C:\Windows\System32\'
        - 'C:\Windows\SystemTemp\'
        - 'C:\Windows\SysWOW64\'
        - 'C:\Windows\uus\'
        - 'C:\Windows\WinSxS\'
filter_optional_system32:
    Image|contains: '\SystemRoot\System32\'
filter_main_powershell:
    Image|contains:
        - 'C:\Program Files\PowerShell\7\'
        - 'C:\Program Files\PowerShell\7-preview\'
        - 'C:\Program Files\WindowsApps\Microsoft.PowerShellPreview'
        - '\AppData\Local\Microsoft\WindowsApps\Microsoft.PowerShellPreview' # pwsh installed from Microsoft Store
    Image|endswith: '\pwsh.exe'
filter_main_wsl_programfiles:
    Image|startswith:
        - 'C:\Program Files\WindowsApps\MicrosoftCorporationII.WindowsSubsystemForLinux'
        - 'C:\Program Files\WSL\'
    Image|endswith: '\wsl.exe'
filter_main_wsl_appdata:
    Image|startswith: 'C:\Users\'
    Image|contains: '\AppData\Local\Microsoft\WindowsApps\'
    Image|endswith: '\wsl.exe'
condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*

False positives (as the rule lists them)

• Unknown

Tags

• attack.stealth
• attack.t1036

MITRE ATT&CK ids this rule names

• T1036

Related rules

• be58d2e2-06c8-4f58-b666-b99f6dc3b6cd (derived)

References

• https://twitter.com/GelosSnake/status/934900723426439170
• https://asec.ahnlab.com/en/39828/
• https://www.splunk.com/en_us/blog/security/inno-setup-malware-redline-stealer-campaign.html

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_susp_system_exe_anomaly.yml