Query: detect Detects the creation of a file with an uncommon extension in an Office application startup folder in logs
Matching passage: Sigma rule: Detects the creation of a file with an uncommon extension in an Office application startup folder. Logsource: windows / file_event. Rule: title: Uncommon File Created In Office Startup Folder id: a10a2c40-2c4d-49f8-b557-1a946bc55d9d status: test description: Detects the creation of a file with an uncommon extension in an Office application startup folder references: - https://app.any.run/tasks/d6fe6624-6ef8-485d-aa75-3d1bdda2a08c/ - http://addbalance.com/word/startup.htm - https://answers.microsoft.com/en-us/msoffice/forum/all/document-in-word-startup-folder-doesnt-open-when/44ab0932-2917-4150-8cdc-2f2cf39e86f3 - https://en.wikipedia.org/wiki/List_of_Microsoft_Office_filename_extensions author: frack113, Nasreddine Bencherchali (Nextron Systems) date: 2022-06-05 modified: 2023-12-13 tags: - attack.resource-development - attack.t1587.001 logsource: product: windows category: file_event detection: selection_word_paths: - TargetFilename|contains: \Microsoft\Word\STARTUP - TargetFilename|contains|all: - \Office - \Program Files - \STARTUP filter_exclude_word_ext: TargetFilename|endswith: - .docb - .docm - .docx - .dotm - .mdb - .mdw - .pdf - .wll - .wwl selection_excel_paths: - TargetFilename|contains: \Microsoft\Excel\XLSTART - TargetFilename|contains|all: - \Office - \Program Files - \XLSTART filter_exclude_excel_ext: TargetFilename|endswith: - .xll - .xls - .xlsm - .xlsx - .xlt - .xltm - .xlw filter_main_office_click_to_run: Image|contains: :\Program Files\Common Files\Microsoft Shared\ClickToRun\ Image|endswith: \OfficeClickToRun.exe filter_main_office_apps: Image|contains: - :\Program Files\Microsoft Office\ - :\Program Files (x86)\Microsoft Office\ Image|endswith: - \winword.exe - \excel.exe condition: ((selection_word_paths and not filter_exclude_word_ext) or (selection_excel_paths and not filter_exclude_excel_ext)) and not 1 of filter_main_* falsepositives: - False positive might stem from rare extensions used by other Office utilities. 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: Msiexec Quiet Installation id: 79a87aa6-e4bd-42fc-a5bb-5e6fbdcd62f5 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/1583914244344799235 author: frack113 date: 2022-01-16 modified: 2026-07-28 tags: - attack.stealth - attack.t1218.007 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: \msiexec.exe - OriginalFileName: msiexec.exe selection_cli: CommandLine|contains|windash: - -i - -package - -a - -j selection_quiet: CommandLine|contains|windash: -q filter_main_system_temp: ParentImage|startswith: C:\Windows\Temp\ filter_main_ccm: ParentImage: C:\Windows\CCM\Ccm32BitLauncher.exe IntegrityLevel: - System - S-1-16-16384 filter_optional_user_temp: ParentImage|startswith: C:\Users\ ParentImage|contains: \AppData\Local\Temp\ filter_optional_wsl: ParentImage|endswith: C:\Windows\System32\wsl.exe Image|endswith: C:\Windows\System32\msiexec.exe condition: all of selection_* and not 1 of filter_main_* and not 1 of filter_optional_* falsepositives: - WindowsApps installing updates via the quiet flag level: medium