Detectionhightest
System File Execution Location Anomaly
Detects the execution of a Windows system binary that is usually located in the system folder from an uncommon location.
Convert In Phoenix Studio
Open this Sigma rule in the converter with the YAML preloaded and ready for backend selection.
Launch
Florian Roth (Nextron Systems), Patrick Bareiss, Anton Kutepov, oscd.community, Nasreddine Bencherchali (Nextron Systems)Created Mon Nov 27Updated Thu Feb 12e4a6b256-3e47-40fc-89d2-7a477edd6915windows
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation
Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.
Detection Logic
Detection Logic6 selectors
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'
- '\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
Unknown
False positive likelihood has not been assessed. Additional context may be needed during triage.
MITRE ATT&CK
Tactics
Techniques
Rule Metadata
Rule ID
e4a6b256-3e47-40fc-89d2-7a477edd6915
Status
test
Level
high
Type
Detection
Created
Mon Nov 27
Modified
Thu Feb 12
Author
Path
rules/windows/process_creation/proc_creation_win_susp_system_exe_anomaly.yml
Raw Tags
attack.defense-evasionattack.t1036