Query: Sigma rule for Detects Windows executables that write files with suspicious extensions
Matching passage: Sigma rule: Detects Windows executables that write files with suspicious extensions. Logsource: windows / file_event. Rule: title: Windows Binaries Write Suspicious Extensions id: b8fd0e93-ff58-4cbd-8f48-1c114e342e62 related: - id: 1277f594-a7d1-4f28-a2d3-73af5cbeab43 type: derived status: test description: Detects Windows executables that write files with suspicious extensions references: - Internal Research author: Nasreddine Bencherchali (Nextron Systems) date: 2022-08-12 modified: 2025-10-07 tags: - attack.stealth - attack.t1036 logsource: category: file_event product: windows detection: selection_generic: Image|endswith: - \csrss.exe - \lsass.exe - \RuntimeBroker.exe - \sihost.exe - \smss.exe - \wininit.exe - \winlogon.exe TargetFilename|endswith: - .bat - .dll - .exe - .hta - .iso - .ps1 - .txt - .vbe - .vbs selection_special: Image|endswith: - \dllhost.exe - \rundll32.exe - \svchost.exe TargetFilename|endswith: - .bat - .hta - .iso - .ps1 - .vbe - .vbs filter_main_AppLockerPolicyTest: Image: C:\Windows\System32\dllhost.exe TargetFilename|contains|all: - :\Users\ - \AppData\Local\Temp\__PSScriptPolicyTest_ TargetFilename|endswith: .ps1 filter_main_script_gpo_machine: Image: C:\Windows\system32\svchost.exe TargetFilename|contains|all: - C:\Windows\System32\GroupPolicy\DataStore\ - \sysvol\ - \Policies\ - \Machine\Scripts\Startup\ TargetFilename|endswith: - .ps1 - .bat filter_main_clipchamp: Image: C:\Windows\system32\svchost.exe TargetFilename|contains|all: - C:\Program Files\WindowsApps\Clipchamp - .ps1 filter_main_powershell_preview: Image: - C:\Windows\system32\svchost.exe - C:\Windows\SysWOW64\svchost.exe TargetFilename|startswith: - C:\Program Files\WindowsApps\Microsoft.PowerShellPreview - C:\Program Files (x86)\WindowsApps\Microsoft.PowerShellPreview TargetFilename|endswith: .ps1 condition: 1 of selection_* and not 1 of filter_main_* falsepositives: - Unknown level: high
Near-miss passage: Sigma rule: Detects processes loading the non-existent DLL "ShellChromeAPI". One known example is the "DeviceEnroller" binary in com. Logsource: windows / image_load. Rule: title: DLL Sideloading Of ShellChromeAPI.DLL id: ee4c5d06-3abc-48cc-8885-77f1c20f4451 related: - id: e173ad47-4388-4012-ae62-bd13f71c18a8 type: similar status: test description: 'Detects processes loading the non-existent DLL "ShellChromeAPI". One known example is the "DeviceEnroller" binary in combination with the "PhoneDeepLink" flag tries to load this DLL. Adversaries can drop their own renamed DLL and execute it via DeviceEnroller.exe using this parameter ' references: - https://mobile.twitter.com/0gtweet/status/1564131230941122561 - https://strontic.github.io/xcyclopedia/library/DeviceEnroller.exe-24BEF0D6B0ECED36BB41831759FDE18D.html author: Nasreddine Bencherchali (Nextron Systems) date: 2022-12-01 tags: - attack.persistence - attack.privilege-escalation - attack.execution - attack.stealth - attack.t1574.001 logsource: category: image_load product: windows detection: selection: ImageLoaded|endswith: \ShellChromeAPI.dll condition: selection falsepositives: - Unknown level: high