Query: detect Detects the creation of files with an executable or script extension by an Office application. in logs
Matching passage: Sigma rule: Detects the creation of files with an executable or script extension by an Office application.. Logsource: windows / file_event. Rule: title: File With Uncommon Extension Created By An Office Application id: c7a74c80-ba5a-486e-9974-ab9e682bc5e4 status: test description: Detects the creation of files with an executable or script extension by an Office application. references: - https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/ - https://github.com/vadim-hunter/Detection-Ideas-Rules/blob/02bcbfc2bfb8b4da601bb30de0344ae453aa1afe/Threat%20Intelligence/The%20DFIR%20Report/20210329_Sodinokibi_(aka_REvil)_Ransomware.yaml author: Vadim Khrykov (ThreatIntel), Cyb3rEng (Rule), Nasreddine Bencherchali (Nextron Systems) date: 2021-08-23 modified: 2025-10-17 tags: - attack.t1204.002 - attack.execution logsource: product: windows category: file_event detection: selection1: Image|endswith: - \excel.exe - \msaccess.exe - \mspub.exe - \powerpnt.exe - \visio.exe - \winword.exe selection2: TargetFilename|endswith: - .bat - .cmd - .com - .dll - .exe - .hta - .ocx - .proj - .ps1 - .scf - .scr - .sys - .vbe - .vbs - .wsf - .wsh filter_main_localassembly: TargetFilename|contains: \AppData\Local\assembly\tmp\ TargetFilename|endswith: .dll filter_optional_webservicecache: TargetFilename|contains|all: - C:\Users\ - \AppData\Local\Microsoft\Office\ - \WebServiceCache\AllUsers TargetFilename|endswith: .com filter_optional_webex: Image|endswith: \winword.exe TargetFilename|contains: \AppData\Local\Temp\webexdelta\ TargetFilename|endswith: - .dll - .exe filter_optional_backstageinappnavcache: TargetFilename|contains|all: - C:\Users\ - \AppData\Local\Microsoft\Office\ - \BackstageInAppNavCache\ TargetFilename|endswith: .com condition: all of selection* and not 1 of filter_main_* and not 1 of filter_optional_* falsepositives: - Unknown level: high
Near-miss passage: Sigma rule: Detects attempts to install unsigned MSIX/AppX packages using the -AllowUnsigned parameter via AppXDeployment-Server eve. Logsource: windows / appxdeployment-server. Rule: title: Windows AppX Deployment Unsigned Package Installation id: 9a025188-6f2d-42f8-bb2f-d3a83d24a5af related: - id: 37651c2a-42cd-4a69-ae0d-22a4349aa04a type: similar - id: 975b2262-9a49-439d-92a6-0709cccdf0b2 type: similar status: experimental description: Detects attempts to install unsigned MSIX/AppX packages using the -AllowUnsigned parameter via AppXDeployment-Server events references: - https://docs.microsoft.com/en-us/powershell/module/appx/add-appxpackage - https://www.splunk.com/en_us/blog/security/msix-weaponization-threat-detection-splunk.html author: Michael Haag, Swachchhanda Shrawan Poudel (Nextron Systems) date: 2025-11-03 tags: - attack.execution - attack.defense-impairment - attack.t1204.002 - attack.t1553.005 logsource: product: windows service: appxdeployment-server detection: selection: EventID: 603 Flags: '8388608' condition: selection falsepositives: - Legitimate installation of unsigned packages for legitimate purposes such as development or testing level: medium