Private Key File Reconnaissance via Command Line

This rule detects attempts to discover private key files using command-line tools such as `cmd.exe`, `powershell.exe`, or `findstr.exe`. It specifically looks for commands that include common private key file extensions like .key, .pgp, .gpg, .ppk, .p12, .pem, .pfx, .cer, .p7b, and .asc. This activity is indicative of an adversary searching for insecurely stored credentials on a compromised system.