Query: alert when Detects suspicious PowerShell download command
Matching passage: Sigma rule: Detects suspicious PowerShell download command. Logsource: windows / ps_script. Rule: title: Suspicious PowerShell Download - Powershell Script id: 403c2cc0-7f6b-4925-9423-bfa573bed7eb related: - id: 65531a81-a694-4e31-ae04-f8ba5bc33759 type: derived status: test description: Detects suspicious PowerShell download command references: - https://learn.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadstring?view=net-8.0 - https://learn.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadfile?view=net-8.0 author: Florian Roth (Nextron Systems) date: 2017-03-05 modified: 2022-12-02 tags: - attack.execution - attack.t1059.001 logsource: product: windows category: ps_script definition: 'Requirements: Script Block Logging must be enabled' detection: webclient: ScriptBlockText|contains: System.Net.WebClient download: ScriptBlockText|contains: - .DownloadFile( - .DownloadFileAsync( - .DownloadString( - .DownloadStringAsync( condition: webclient and download falsepositives: - PowerShell scripts that download content from the Internet level: medium
Near-miss passage: Sigma rule: Detects potential COM object hijacking via modification of default system CLSID.. Logsource: windows / registry_set. Rule: title: COM Object Hijacking Via Modification Of Default System CLSID Default Value id: 790317c0-0a36-4a6a-a105-6e576bf99a14 related: - id: 3d968d17-ffa4-4bc0-bfdc-f139de76ce77 type: obsolete - id: a0ff33d8-79e4-4cef-b4f3-9dc4133ccd12 type: obsolete status: experimental description: Detects potential COM object hijacking via modification of default system CLSID. references: - https://www.microsoft.com/security/blog/2022/07/27/untangling-knotweed-european-private-sector-offensive-actor-using-0-day-exploits/ (idea) - https://unit42.paloaltonetworks.com/snipbot-romcom-malware-variant/ - https://blog.talosintelligence.com/uat-5647-romcom/ - https://global.ptsecurity.com/analytics/pt-esc-threat-intelligence/darkhotel-a-cluster-of-groups-united-by-common-techniques - https://threatbook.io/blog/Analysis-of-APT-C-60-Attack-on-South-Korea - https://catalyst.prodaft.com/public/report/inside-the-latest-espionage-campaign-of-nebulous-mantis - https://github.com/rtecCyberSec/BitlockMove - https://cert.gov.ua/article/6284080 - https://securelist.com/forumtroll-apt-hacking-team-dante-spyware/117851/ author: Nasreddine Bencherchali (Nextron Systems) date: 2024-07-16 modified: 2025-11-10 tags: - attack.privilege-escalation - attack.persistence - attack.t1546.015 logsource: category: registry_set product: windows detection: selection_target_root: TargetObject|contains: \CLSID\ TargetObject|endswith: - \InprocServer32\(Default) - \LocalServer32\(Default) selection_target_builtin_clsid: TargetObject|contains: - \{1f486a52-3cb1-48fd-8f50-b8dc300d9f9d}\ - \{2155fee3-2419-4373-b102-6843707eb41f}\ - \{4590f811-1d3a-11d0-891f-00aa004b2e24}\ - \{4de225bf-cf59-4cfc-85f7-68b90f185355}\ - \{ddc05a5a-351a-4e06-8eaf-54ec1bc2dcea}\ - \{F56F6FDD-AA9D-4618-A949-C1B91AF43B1A}\ - \{F82B4EF1-93A9-4DDE-8015-F7950A1A6E31}\ - \{7849596a-48ea-486e-8937-a2a3009f31a9}\ - \{0b91a74b-ad7c-4a9d-b563-29eef9167172}\ - \{603D3801-BD81-11d0-A3A5-00C04FD706EC}\ - \{30D49246-D217-465F-B00B-AC9DDD652EB7}\ - \{A7A63E5C-3877-4840-8727-C1EA9D7A4D50}\ - \{2227A280-3AEA-1069-A2DE-08002B30309D}\ - \{2DEA658F-54C1-4227-AF9B-260AB5FC3543}\ - \{AA509086-5Ca9-4C25-8F95-589D3C07B48A}\ selection_susp_location_1: Details|contains: - :\Perflogs\ - \AppData\Local\ - \Desktop\ - \Downloads\ - \Microsoft\Windows\Start Menu\Programs\Startup\ - \System32\spool\drivers\color\ - \Temporary Internet - \Users\Public\ - \Windows\Temp\ - '%appdata%' - '%temp%' - '%tmp%' selection_susp_location_2: - Details|contains|all: - :\Users\ -