Query: write Sigma for Detects creation of Microsoft Office files inside of one of the default startup folders in order to achieve persistence.
Matching passage: Sigma rule: Detects creation of Microsoft Office files inside of one of the default startup folders in order to achieve persistence.. Logsource: windows / file_event. Rule: title: Potential Persistence Via Microsoft Office Startup Folder id: 0e20c89d-2264-44ae-8238-aeeaba609ece status: test description: Detects creation of Microsoft Office files inside of one of the default startup folders in order to achieve persistence. references: - https://insight-jp.nttsecurity.com/post/102hojk/operation-restylink-apt-campaign-targeting-japanese-companies - https://learn.microsoft.com/en-us/office/troubleshoot/excel/use-startup-folders author: Max Altgelt (Nextron Systems), Nasreddine Bencherchali (Nextron Systems) date: 2022-06-02 modified: 2023-06-22 tags: - attack.persistence - attack.t1137 logsource: category: file_event product: windows detection: selection_word_paths: - TargetFilename|contains: \Microsoft\Word\STARTUP - TargetFilename|contains|all: - \Office - \Program Files - \STARTUP selection_word_extension: TargetFilename|endswith: - .doc - .docm - .docx - .dot - .dotm - .rtf selection_excel_paths: - TargetFilename|contains: \Microsoft\Excel\XLSTART - TargetFilename|contains|all: - \Office - \Program Files - \XLSTART selection_excel_extension: TargetFilename|endswith: - .xls - .xlsm - .xlsx - .xlt - .xltm filter_main_office: Image|endswith: - \WINWORD.exe - \EXCEL.exe condition: (all of selection_word_* or all of selection_excel_*) and not filter_main_office falsepositives: - Loading a user environment from a backup or a domain controller - Synchronization of templates level: high
Near-miss passage: Sigma rule: Detects the execution of a renamed binary often used by attackers or malware leveraging new Sysmon OriginalFileName data. Logsource: windows / process_creation. Rule: title: Potential Defense Evasion Via Rename Of Highly Relevant Binaries id: 0ba1da6d-b6ce-4366-828c-18826c9de23e related: - id: 36480ae1-a1cb-4eaa-a0d6-29801d7e9142 type: similar - id: 2569ed8c-1147-498a-9b8c-2ad3656b10ed type: derived - id: a7a7e0e5-1d57-49df-9c58-9fe5bc0346a2 type: obsolete - id: d178a2d7-129a-4ba4-8ee6-d6e1fecd5d20 type: obsolete - id: d4d2574f-ac17-4d9e-b986-aeeae0dc8fe2 type: obsolete status: test description: Detects the execution of a renamed binary often used by attackers or malware leveraging new Sysmon OriginalFileName datapoint. references: - https://mgreen27.github.io/posts/2019/05/12/BinaryRename.html - https://mgreen27.github.io/posts/2019/05/29/BinaryRename2.html - https://www.trendmicro.com/vinfo/hk-en/security/news/cybercrime-and-digital-threats/megacortex-ransomware-spotted-attacking-enterprise-networks - https://twitter.com/christophetd/status/1164506034720952320 - https://threatresearch.ext.hp.com/svcready-a-new-loader-reveals-itself/ - https://www.huntress.com/blog/malicious-browser-extention-crashfix-kongtuke author: Matthew Green - @mgreen27, Florian Roth (Nextron Systems), frack113 date: 2019-06-15 modified: 2026-06-29 tags: - attack.stealth - attack.t1036.003 - car.2013-05-009 logsource: category: process_creation product: windows detection: selection: - Description: Execute processes remotely - Product: Sysinternals PsExec - Description|startswith: - Windows PowerShell - pwsh - OriginalFileName: - certutil.exe - cmstp.exe - cscript.exe - IE4UINIT.EXE - finger.exe - mshta.exe - msiexec.exe - msxsl.exe - powershell_ise.exe - powershell.exe - psexec.c - psexec.exe - psexesvc.exe - pwsh.dll - reg.exe - regsvr32.exe - rundll32.exe - WerMgr - wmic.exe - wscript.exe filter: Image|endswith: - \certutil.exe - \cmstp.exe - \cscript.exe - \ie4uinit.exe - \finger.exe - \mshta.exe - \msiexec.exe - \msxsl.exe - \powershell_ise.exe - \powershell.exe - \psexec.exe - \psexec64.exe - \psexec64a.exe - \PSEXESVC.exe - \pwsh.exe - \reg.exe - \regsvr32.exe - \rundll32.exe - \wermgr.exe - \wmic.exe - \wscript.exe condition: selection and not filter falsepositives: - Custom applications use renamed binaries adding slight change to binary name. Typically this is easy to spot and add to whitelist - PsExec installed via Windows Store doesn't contain original filename field (False negative) level: high regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_renamed_binary_highly_relevant/info.yml