Query: write Sigma for Detects calls to base64 encoded WMI class such as "Win32_ShadowCopy", "Win32_ScheduledJob", etc.
Matching passage: Sigma rule: Detects calls to base64 encoded WMI class such as "Win32_ShadowCopy", "Win32_ScheduledJob", etc.. Logsource: windows / process_creation. Rule: title: PowerShell Base64 Encoded WMI Classes id: 1816994b-42e1-4fb1-afd2-134d88184f71 related: - id: 47688f1b-9f51-4656-b013-3cc49a166a36 type: obsolete status: test description: Detects calls to base64 encoded WMI class such as "Win32_ShadowCopy", "Win32_ScheduledJob", etc. references: - https://github.com/Neo23x0/Raccine/blob/20a569fa21625086433dcce8bb2765d0ea08dcb6/yara/mal_revil.yar author: Christian Burkard (Nextron Systems), Nasreddine Bencherchali (Nextron Systems) date: 2023-01-30 tags: - attack.execution - attack.stealth - attack.t1059.001 - attack.t1027 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: - \powershell.exe - \pwsh.exe - OriginalFileName: - PowerShell.EXE - pwsh.dll selection_cli_shadowcopy: CommandLine|contains: - VwBpAG4AMwAyAF8AUwBoAGEAZABvAHcAYwBvAHAAeQ - cAaQBuADMAMgBfAFMAaABhAGQAbwB3AGMAbwBwAHkA - XAGkAbgAzADIAXwBTAGgAYQBkAG8AdwBjAG8AcAB5A - V2luMzJfU2hhZG93Y29we - dpbjMyX1NoYWRvd2NvcH - XaW4zMl9TaGFkb3djb3B5 selection_cli_scheduledJob: CommandLine|contains: - VwBpAG4AMwAyAF8AUwBjAGgAZQBkAHUAbABlAGQASgBvAGIA - cAaQBuADMAMgBfAFMAYwBoAGUAZAB1AGwAZQBkAEoAbwBiA - XAGkAbgAzADIAXwBTAGMAaABlAGQAdQBsAGUAZABKAG8AYg - V2luMzJfU2NoZWR1bGVkSm9i - dpbjMyX1NjaGVkdWxlZEpvY - XaW4zMl9TY2hlZHVsZWRKb2 selection_cli_process: CommandLine|contains: - VwBpAG4AMwAyAF8AUAByAG8AYwBlAHMAcw - cAaQBuADMAMgBfAFAAcgBvAGMAZQBzAHMA - XAGkAbgAzADIAXwBQAHIAbwBjAGUAcwBzA - V2luMzJfUHJvY2Vzc - dpbjMyX1Byb2Nlc3 - XaW4zMl9Qcm9jZXNz selection_cli_useraccount: CommandLine|contains: - VwBpAG4AMwAyAF8AVQBzAGUAcgBBAGMAYwBvAHUAbgB0A - cAaQBuADMAMgBfAFUAcwBlAHIAQQBjAGMAbwB1AG4AdA - XAGkAbgAzADIAXwBVAHMAZQByAEEAYwBjAG8AdQBuAHQA - V2luMzJfVXNlckFjY291bn - dpbjMyX1VzZXJBY2NvdW50 - XaW4zMl9Vc2VyQWNjb3Vud selection_cli_loggedonuser: CommandLine|contains: - VwBpAG4AMwAyAF8ATABvAGcAZwBlAGQATwBuAFUAcwBlAHIA - cAaQBuADMAMgBfAEwAbwBnAGcAZQBkAE8AbgBVAHMAZQByA - XAGkAbgAzADIAXwBMAG8AZwBnAGUAZABPAG4AVQBzAGUAcg - V2luMzJfTG9nZ2VkT25Vc2Vy - dpbjMyX0xvZ2dlZE9uVXNlc - XaW4zMl9Mb2dnZWRPblVzZX condition: selection_img and 1 of selection_cli_* falsepositives: - Unknown level: high
Near-miss passage: Sigma rule: Adversaries may abuse msiexec.exe to proxy execution of malicious payloads. Msiexec.exe is the command-line utility for. Logsource: windows / process_creation. Rule: title: Suspicious Msiexec Execute Arbitrary DLL id: 6f4191bb-912b-48a8-9ce7-682769541e6d status: test description: 'Adversaries may abuse msiexec.exe to proxy execution of malicious payloads. Msiexec.exe is the command-line utility for the Windows Installer and is thus commonly associated with executing installation packages (.msi) ' references: - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/msiexec - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1218.007/T1218.007.md - https://twitter.com/_st0pp3r_/status/1583914515996897281 author: frack113 date: 2022-01-16 modified: 2026-01-09 tags: - attack.stealth - attack.t1218.007 logsource: category: process_creation product: windows detection: selection: Image|endswith: \msiexec.exe CommandLine|contains|windash: ' /Y' filter_main_legit_path: CommandLine|contains: - \MsiExec.exe" /Y "C:\Program Files\ - \MsiExec.exe" /Y "C:\Program Files (x86)\ - \MsiExec.exe" /Y "C:\Windows\System32\ - \MsiExec.exe" /Y "C:\Windows\SysWOW64\ condition: selection and not 1 of filter_main_* falsepositives: - Legitimate script level: medium