Command and Control (TA0011)(external, opens in a new tab or window)
text code block:sequence by process.entity_id with maxspan=30s [network where host.os.type == "windows" and process.name : ("powershell.exe", "pwsh.exe", "powershell_ise.exe") and network.protocol == "dns" and not dns.question.name : ( "*.microsoft.com", "*.azureedge.net", "*.powershellgallery.com", "*.windowsupdate.com", "metadata.google.internal", "dist.nuget.org", "artifacts.elastic.co", "*.digicert.com", "*.chocolatey.org", "outlook.office365.com", "cdn.oneget.org", "ci.dot.net", "packages.icinga.com", "login.microsoftonline.com", "*.gov", "*.azure.com", "*.python.org", "dl.google.com", "sensor.cloud.tenable.com", "*.azurefd.net", "*.office.net", "*.anac*", "aka.ms", "dot.net", "*.visualstudio.com", "*.local") and not user.id == "S-1-5-18" and /* Filter out NetBIOS/LLMNR-style names (e.g. host, localhost, etc.) */ dns.question.name regex """.*\.[a-zA-Z]{2,5}"""] [file where host.os.type == "windows" and event.type == "creation" and process.name : "powershell.exe" and (file.extension : ("exe", "dll", "ps1", "bat") or file.Ext.header_bytes : "4d5a*") and not file.name : "__PSScriptPolicy*.ps1" and not file.path : ( "?:\\Users\\*\\AppData\\Local\\Temp\\????????.dll", "?:\\Users\\*\\AppData\\Local\\Temp\\*\\????????.dll", "?:\\Windows\\TEMP\\ansible-tmp-*\\AnsiballZ*.ps1" ) and not user.id == "S-1-5-18"]
Install detection rules in Elastic Security
Detect Remote File Download via PowerShell in the Elastic Security detection engine by installing this rule into your Elastic Stack.
To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).