Date: 01/17/2025
Severity: Medium
Summary
"Suspicious Invoke-WebRequest Execution" refers to the detection of an unusual use of the Invoke-WebRequest cmdlet, a PowerShell command typically used to send HTTP requests. The suspicion arises when the output of the command is directed to a suspicious location, which may indicate malicious intent, such as downloading or exfiltrating data to an unauthorized location. This behavior could be a sign of a cyberattack or unauthorized activity.
Indicators of Compromise (IOC) List
Image  | \powershell.exe 
			\pwsh.exe  | 
OriginalFileName  | PowerShell.EXE 
			pwsh.dll  | 
CommandLine  | 'curl ' 'Invoke-WebRequest'  'iwr ' 'wget '  ' -ur'  ' -o' '\AppData\' '\Desktop\' '\Temp\' '\Users\Public\'  '%AppData%'  '%Public%' '%Temp%'  '%tmp%'  ':\Windows\'  | 
Gurucul Threat Detection and Incident Response (TDIR) Queries for Detection
Detection Query 1  | (resourcename in ("Windows Security") AND eventtype = "4688" AND newprocessname IN ("\powershell.exe","\pwsh.exe") AND processname IN ("PowerShell.EXE","pwsh.dll") AND ((commandline like "curl" or commandline like "Invoke-WebRequest" or commandline like "iwr" or commandline like "wget") AND (commandline like "-ur" or commandline like "-o")) AND (commandline like "\AppData" or commandline like "\Desktop" or commandline like "\Temp" or commandline like "\Users\Public" or commandline like "%AppData%" or commandline like "%Public%" or commandline like "%Temp%" or commandline like "%tmp%" or commandline like ":\Windows"))  | 
Detection Query 2  | (technologygroup = "EDR" AND newprocessname IN ("\powershell.exe","\pwsh.exe") AND processname IN ("PowerShell.EXE","pwsh.dll") AND ((commandline like "curl" or commandline like "Invoke-WebRequest" or commandline like "iwr" or commandline like "wget") AND (commandline like "-ur" or commandline like "-o")) AND (commandline like "\AppData" or commandline like "\Desktop" or commandline like "\Temp" or commandline like "\Users\Public" or commandline like "%AppData%" or commandline like "%Public%" or commandline like "%Temp%" or commandline like "%tmp%" or commandline like ":\Windows"))  | 
Reference: 
https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_powershell_invoke_webrequest_download.yml