Run PowerShell Script from Redirected Input Stream
This rule detects the execution of PowerShell scripts where the script content is provided via a redirected input stream. This technique is often used by adversaries to execute malicious PowerShell code without writing it to a file, which can help evade detection. The rule specifically looks for PowerShell or pwsh executables being run with a command line containing '- <', which signifies input stream redirection.
Sigma

