How to use the command Set-Acl (with examples)

The Set-Acl command is used to change the security descriptor of a specified item, such as a file or a registry key. This command is only available in PowerShell and can be used to modify the security settings of any item that has a security descriptor.

Use case 1: Copy a security descriptor from one file to another

Code:

$OriginAcl = Get-Acl -Path path\to\file
Set-Acl -Path path\to\file -AclObject $OriginAcl

Motivation: In this use case, we want to copy the security descriptor from one file to another file. By using the Get-Acl command, we can retrieve the security descriptor of the first file and store it in a variable called $OriginAcl. Then, we use the Set-Acl command to apply the stored security descriptor to the second file. This ensures that both files have the same security settings.

Explanation:

• $OriginAcl: This variable stores the security descriptor retrieved from the first file using the Get-Acl command.
• Get-Acl -Path path\to\file: This command retrieves the security descriptor of the file specified in the path.
• Set-Acl -Path path\to\file -AclObject $OriginAcl: This command sets the security descriptor of the file specified in the path with the value stored in the $OriginAcl variable.

Example output: No output is shown if the command is executed successfully. The security descriptor of the second file will be updated to match the security descriptor of the first file.

Use case 2: Use the pipeline operator to pass a descriptor

Code:

Get-Acl -Path path\to\file | Set-Acl -Path path\to\file

Motivation: In this use case, we use the pipeline operator to pass the security descriptor directly from the Get-Acl command to the Set-Acl command without the need for an intermediate variable. This provides a more concise way of setting the security descriptor.

Explanation:

• Get-Acl -Path path\to\file: This command retrieves the security descriptor of the file specified in the path and passes it to the next command in the pipeline.
• Set-Acl -Path path\to\file: This command sets the security descriptor of the file specified in the path with the value received from the pipeline.

Example output: No output is shown if the command is executed successfully. The security descriptor of the file will be updated based on the input received from the pipeline.

Conclusion:

The Set-Acl command is a powerful tool for modifying the security settings of files and registry keys. It can be used to copy security descriptors from one item to another and to apply security descriptors received from the pipeline. By understanding the different use cases and their corresponding command syntax, users can effectively manage the security of their files and registry keys using PowerShell.