Suspicious PowerShell Execution
Description
Identifies the execution of PowerShell with suspicious argument values. This behavior is often observed during malware installation leveraging PowerShell.
Query · eql
process where event.action == "start" and process.name : "powershell.exe" and process.parent.executable != null and
not user.id : "S-1-5-18" and
/*
following exclusions are covered by other rules
- Suspicious Execution via Windows Management Instrumentation
- Suspicious Windows Schedule Child Process
- PowerShell Obfuscation Spawned via Microsoft Office
- Suspicious PowerShell Execution via Windows Scripts
*/
not (process.parent.executable :
("?:\\Windows\\System32\\svchost.exe",
"?:\\Windows\\System32\\wbem\\WmiPrvSe.exe",
"?:\\Program Files\\*.exe",
"?:\\Program Files (x86)\\*.exe",
"?:\\Users\\*\\AppData\\Local\\gitkraken\\app-*\\gitkraken.exe",
"?:\\Windows\\System32\\taskeng.exe",
"?:\\Windows\\cybercnsagent\\cybercnsagent.exe",
"?:\\Windows\\SysWOW64\\WindowsPowerShell\\*\\powershell_ise.exe",
"?:\\Windows\\System32\\WindowsPowerShell\\*\\powershell_ise.exe",
"?:\\ProgramData\\Microsoft\\Windows Defender Advanced Threat Protection\\Platform\\*\\SenseIR.exe") and not process.parent.name : "java.exe") and
not process.parent.name : ("wscript.exe", "cscript.exe") and
not (process.args:"-NonInteractive" and process.args :"-InputFormat") and
not (process.args : ("RemoteSigned", "-ExecutionPolicy", "write-host") and
not process.parent.name : ("explorer.exe", "python.exe", "cmd.exe")) and
not process.args : "[System.Text.Encoding]::UTF8.GetString([System.Convert]::FromBase64String('cGFzc3dvcmQ='))" and
not (process.command_line : "*echo ~/.ansible/tmp/ansible-tmp*" and process.parent.executable : "C:\\Windows\\System32\\OpenSSH\\sshd.exe") and
not (process.args : "$OutputEncoding = [System.Text.Encoding]::UTF8; $b64='eyJjb252ZXJzYXRpb25faWQiOiJ*" and process.parent.name : "Cursor.exe") and
not process.command_line :
("*ConvertTo-Json*Write-Host*",
"*BrowserExtension.dll*WebCompanion.BrowserExtension*",
"*-ExecutionPolicy*Write-Verbose*",
"*webClient.Headers.add*",
"*System.Management.Automation.Host.Size*",
"*JABQAHIAbwBnAHIAZQBzAHMAUAByAGUAZgBlAHIAZQ*",
"*chocolatey.org*",
"*Get-WmiObject*",
"*artifacts.elastic.co*",
"*officecdn.microsoft.com*",
"*CgAgACAAIAAgACAAIAAgACAAJABTAGMAcgBpAHAAdAAgACA*",
"*Program Files*",
"*).Access.IdentityReference;$defaults*",
"*https://repo.maven.apache.org*",
"*\\CSIWorking\\system\\WinSCP\\winscp.com*",
"*@Files.onetech.cc*",
"*Register-AzureADConnectHealthADDSAgent*",
"*\\ProgramData\\Microsoft\\LogConverter\\*",
"*WinSCP.com*",
"*SNC_isWmi*",
"*--app-id=memtime-*",
"*BkAGEAdABhAGIAYQBzAGUALgB3AGkAbgBkAG8AdwBzAC4AbgBlAHQA*",
"*FsAdgBlAHIAcwBpAG8AbgBdACQAbQBpAG4AaQBtAHUAbQBWAGUAcgBzAGkAbwBuACAAPQAgACcAMgAuADIALgAwACcA*",
"*https://tshf.sas.com/techsup/download/hotfix/*",
"*scripts\\buildsystems\\msbuild*",
"*.vscode\\extensions\\ms-dynamics-smb*",
"*$ErrorActionPreference*$adsiMember*",
"*$ErrorActionPreference*$rgx_log4j*",
"*$env:APPDATA\"+'\\Browser Assistant\\*",
"*APPDATA\"+'/Browser Extension/BE.txt*",
"*$env:APPDATA\"+'/BBWC/*",
"*ReadAllBytes($w+'Newtonsoft.Json.dll*",
"*https://go.microsoft.com/fwlink*",
"*krsfile:////LOBCS*",
"*ProgramData\\VinitySoft Data\\MariaDb\\*",
"*\\Temp\\claude\\claude-pwd-ps-*",
"*https://10.55.138.214:443/downloads/*",
"\"C:\\Windows\\SysWOW64\\WindowsPowerShell\\v1.0\\powershell.exe\" -noexit -command \"[reflection.assembly]::loadFrom('.\\RD-PSAPI.dll') | import-module\"",
"*-noni -nop -w 1 -enc *AEUAbABhAHMAdABpAGMAfABUAHIAZQBsAGwAaQB4ACIA*",
"*-noni -nop -w 1 -enc *AEUAbABhAHMAdABpAGMAIABBAGcAZQBuAHQAIgA=*",
"*JABjAGwAcwA9ACcATQBvAHUAcwBlACcAOwAKACAAIABHAGUAdAAtAEMAaQBtAEkAbgBzAHQAYQBuAGMAZQAgAFcAaQBuADMAMgBfAFAAbgBQAEUAbgB0AGkAdAB5ACAALQBGAGkAb*",
"*JABjAGwAcwA9ACcASwBlAHkAYgBvAGEAcgBkACcAOwAKACAAIABHAGUAdAAtAEMAaQBtAEkAbgBzAHQAYQBuAGMAZQAgAFcAaQBuADMAMgBfAFAAbgBQAEUAbgB0AGkAdAB5ACAALQBGAGkAb*",
"*JABjAHYAIAA9ACAARwBlAHQALQBJAHQAZQBtAFAAcgBvAHAAZQByAHQAeQAgACcASABLAEwATQA6AFwAUwBPAEYAVABXAEEAUgBFAFwATQBpAGMAcgBvAHMAbwBmAHQAXABXAGkAbgBkAG8AdwBzACAATgBUAFwAQwB1AHIAcgBlAG4AdABWAGUAcgBzAGkAbwBuACcACgAiACQAKAAkAGMAdgAuAFAAcgBvAGQAdQBjAHQATgBhAG0AZQApAHwAJAAoACQAYwB2AC4ARABpAHMAcABsAGEAeQBWAGUAcgBzAGkAbwBuACkAf*",
/* inventory tooling checking the installed Chrome version: $ErrorActionPreference='silentlycontinue'; $tmp = (Get-Item -Path "$env:PROGRAMFILES\Google\Chrome\Application\chrome.exe") */
"*JABFAHIAcgBvAHIAQQBjAHQAaQBvAG4AUAByAGUAZgBlAHIAZQBuAGMAZQA9ACcAcwBpAGwAZQBuAHQAbAB5AGMAbwBuAHQAaQBuAHUAZQAnADsAIAAkAHQAbQBwACAAPQAgACgARwBlAHQALQBJAHQAZQBtACAALQBQAGEAdABoACAAIgAkAGUAbgB2ADoAUABSAE8ARwBSAEEATQBGAEkATABFAFMAXABHAG8AbwBnAGwAZQBcAEMAaAByAG8AbQBlAFwA*",
/* base64 alignment variant of the Az.Accounts minimum version check already excluded above: \n$ErrorActionPreference = 'Stop'\n[version]$minimumVersion = '2.2.0' */
"*CgAkAEUAcgByAG8AcgBBAGMAdABpAG8AbgBQAHIAZQBmAGUAcgBlAG4AYwBlACAAPQAgACcAUwB0AG8AcAAnAAoAWwB2AGUAcgBzAGkAbwBuAF0AJABtAGkAbgBpAG0AdQBtAFYAZQByAHMAaQBvAG4A*") and
not process.parent.args : "([Datetime]::ParseExact($_.InstalledOn," and
not process.command_line : ("PowerShell*hkguTzSCb75g7sJ9ChMcmAOPpeBL9ZJy/tejnoCjT+E=*", "*.LastWriteTime.ToFileTime*", "*New-Object*Net.Mail.SmtpClien*") and
not (process.parent.name : "cmd.exe" and
(process.parent.command_line : "*\\WindowsPowershell\\*\\powershell*" or process.parent.args : ("-Command", "-OutputFormat", "-InputFormat"))) and
not process.parent.name : "powershell.exe" and
not (process.parent.name : "cmd.exe" and process.parent.args : ("*.cmd", "*.bat") and process.command_line: "*Get-Content*Set-Content*") and
not (process.args : "NT\\CurrentVersion').InstallationType;" and process.args : "[System.Text.Encoding]::UTF8.GetBytes($OutStr);") and
not (process.parent.code_signature.trusted == true and process.parent.code_signature.subject_name in ("ControlCase LLC", "HashiCorp, Inc.", "JetBrains s.r.o.", "Johannes Schindelin", "Anomaly Innovations, Inc https://anoma.ly/", "Anthropic, PBC", "Anysphere, Inc.", "Denver Technologies, Inc. dba Warp")) and
not process.parent.command_line : "\"C:\\Windows\\system32\\cmd.exe\" " and
not (process.parent.name : "Cursor.exe" and process.command_line : "* dotnet csharpier format*") and
not (process.parent.name : "codex*.exe" and process.args : "[Console]::OutputEncoding=[System.Text.Encoding]::UTF8;*") and
not process.working_directory : "C:\\ProgramData\\VinitySoft Data\\MariaDb\\" and
not process.parent.executable : ("C:\\Users\\*\node_modules\\@openai\\codex\\bin\\codex-x86_64-pc-windows-msvc.exe",
"C:\\Users\\*\\extensions\\openai.chatgpt-*\\bin\\windows-x86_64\\codex.exe",
"C:\\Users\\*\\AppData\\Local\\Programs\\Microsoft VS Code\\Code.exe",
"C:\\Users\\*\\@openai\\*\\x86_64-pc-windows-msvc\\codex\\codex.exe",
"C:\\Python312\\python.exe",
"?:\\Users\\*\\AppData\\Local\\Programs\\Antigravity\\resources\\app\\extensions\\antigravity\\bin\\language_server_windows_x64.exe",
"?:\\Users\\*\\AppData\\Local\\Python\\bin\\python.exe",
"?:\\Users\\*\\AppData\\Local\\Programs\\Python\\Python*\\python.exe",
"?:\\Users\\*\\AppData\\Local\\Python\\pythoncore-*\\python.exe",
"D:\\Antigravity\\resources\\app\\extensions\\antigravity\\bin\\language_server_windows_x64.exe",
"?:\\Users\\*\\.codex\\.sandbox-bin\\codex-command-runner-*.exe") and
not process.args : ("$w=$env:LOCALAPPDATA+'/OPWC/';[Reflection.Assembly]::Load([System.IO.File]::ReadAllBytes($w+'OperaSharpDLL.dll'));[OperaSharpDLL.Helper]::Startup()",
"IEX (New-Object Net.WebClient).DownloadString('https://install.demo-toolkit.de/dtkupdater.ps1?apikey=*",
"D:\\PowerShell\\webclient.cmd",
"Invoke-WebRequest -Uri https://www.7-zip.org/a/7zr.exe -o '7zr.exe';",
"\"& 'C:\\Program Files (x86)\\combit\\*",
"Get-CimInstance -Namespace root\\wmi -ClassName WmiMonitorID | *",
"& { Add-Type -A 'System.IO.Compression.FileSystem'; [IO.Compression.ZipFile]::CreateFromDirectory*") and
not (process.parent.name : "cmd.exe" and
process.parent.args : ("D:\\PowerShell\\webclient.cmd",
"C:\\Temp\\FST-Robocopy-wEmailNotif.cmd",
"C:\\istip-installation\\install.bat",
"'C:\\ProgramData\\PatchBot\\data\\windows-health-after.json';",
"'C:\\ProgramData\\PatchBot\\data\\windows-updates.json';",
"'C:\\ProgramData\\PatchBot\\data\\windows-updates.json')")) and
not (process.parent.executable : "C:\\Users\\*\\AppData\\Local\\Programs\\Microsoft VS Code\\Code.exe" and process.command_line : "*Windows.UI.Notifications*") and
not (process.parent.executable : "C:\\Users\\*\\.vscode\\extensions\\openai.chatgpt*-win32-x64\\bin\\windows-x86_64\\codex.exe" and process.parent.args == "mcp") and
not (process.parent.executable : "C:\\Windows\\System32\\msiexec.exe" and process.args : "https://go.microsoft.com/fwlink/p/?LinkId=*" and
process.args :"$env:TEMP\\MicrosoftEdgeWebview2Setup.exe") and
not process.args : "chcp 65001;[System.Reflection.Assembly]::LoadWithPartialName('System.Drawing');(New-Object System.Drawing.Text.InstalledFontCollection).Families" and
(
process.command_line :
(
"*^*^*^*^*^*^*^*^*^*",
"*`*`*`*`*",
"*+*+*+*+*+*+*",
"*[char[]](*)*-join*",
"*Base64String*",
"*[*Convert]*",
"*.Compression.*",
"*-join($*",
"*.replace*",
"*MemoryStream*",
"*WriteAllBytes*",
"* -enc *",
"* -ec *",
"* /e *",
"* /enc *",
"* /ec *",
"*WebClient*",
"*DownloadFile*",
"*DownloadString*",
"* iex*",
"*;iex*",
"* iwr*",
"*;iwr *",
"*;saps *",
"* aQB3AHIAIABpA*",
"*Reflection.Assembly*",
"*Assembly.GetType*",
"*$env:temp\\*start*",
"*powercat*",
"*nslookup -q=txt*",
"*$host.UI.PromptForCredential*",
"*Net.Sockets.TCPClient*",
"*curl *;Start*",
"powershell.exe \"<#*",
"*ssh -p *",
"*http*|iex*",
"*@SSL\\DavWWWRoot\\*.ps1*",
"*.lnk*.Seek(0x*",
"*[string]::join(*",
"*[Array]::Reverse($*",
"* hidden $(gc *",
"*=wscri& set*",
"*http'+'s://*",
"*.content|i''Ex*",
"*//:sptth*",
"*//:ptth*",
"*h''t''t''p*",
"*'tp'':''/'*",
"*$env:T\"E\"MP*",
"*;cmd /c $?",
"*s''t''a''r*",
"*$*=Get-Content*AppData*.SubString(*$*",
"*=cat *AppData*.substring(*);*$*",
"*-join'';*|powershell*",
"*.Content;sleep *|powershell*",
"*h\''t\''tp:\''*",
"*-e aQB3AHIAIABp*",
"*iwr *https*).Content*",
"*$env:computername*http*",
"*;InVoKe-ExpRESsIoN $COntent.CONTENt;*",
"*WebClient*example.com*",
"*=iwr $*;iex $*",
"*gc *:*|sc *",
"*gci *-Recurse*start*",
"*Invoke-WebRequest*Start-Process*Hidden*",
"*Invoke-WebRequest*msiexec*"
) or
(process.command_line regex~ """.*p\"?o\"?w\"?e\"?r\"?s\"?h\"?e\"?l\"?l.*""" and not process.command_line : "*powershell*") or
(process.args: "bypass" and process.args : "hidden" and process.command_line : "*start-process*appdata*") or
(process.args : "-c" and process.args : "&{'*") or
(process.args : "-Outfile" and process.args : "Start*") or
(process.args : "-bxor" and process.args : "0x*") or
process.args : "$*$*;set-alias" or
(process.command_line : ("*-encodedCommand*", "*Invoke-webrequest*", "*WebClient*", "*Reflection.Assembly*") and
(process.parent.name : ("explorer.exe", "python*.exe") or
(process.parent.name : "cmd.exe" and
descendant of [process where event.action == "start" and process.name : ("explorer.exe", "python*.exe")])))
)