Powershell Basics

Review of Operating Systems

Linux

• Generic term that refers to different open-source operating systems that are based on the Linux kernel.

• The Linux kernel was originally created by Linux Torvalds in 1991 and open-sourced in 1996.

• A kernel is a piece of software that is designed to act as an intermediate layer between low-level hardware and high-level software, such as an operating system.

Powershell Basics

• New Windows Powershell that combines that old CMD functionality with the new scripting/cmdlet instructions set

• Microsoft shell --> Windows Powershell --> Powershell Core --> Powershell

ISE

• Specialized environment for writing and testing scripts. designed for automation. provides:

  • Script editor

  • console

  • debugging tools

Powershell Variables

$ is used for defining and accessing variables in PowerShell.

Powershell Basic Commands

• https://devblogs.microsoft.com/scripting/table-of-basic-powershell-commands/

• https://www.pdq.com/powershell/

• https://ss64.com/ps/

Get-Alias give the new style PowerShell command name of old style CMD command names.

Execution Policies

A PowerShell safety feature that controls the conditions under which PowerShell loads configuration files and runs scripts. It helps prevent the execution of malicious scripts.

• https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_execution_policies?view=powershell-7.4

AllSigned

• Requires that all scripts and configuration files be signed by a trusted publisher

• Prompts you before running scripts from publishers that you haven't yet classified as trusted or untrusted.

• Risks running signed but malicious scripts.

Bypass

• Nothing is blocked and there are no warning or prompts

RemoteSigned

• Requires a digital signature from a trusted publisher on scripts and configuration

• doesn't require digital signatures on scripts that are written on the local computer.