<PackageReference Include="System.Security.Permissions" Version="10.0.0-preview.3.25171.5" />

SiteIdentityPermissionAttribute

public sealed class SiteIdentityPermissionAttribute : CodeAccessSecurityAttribute
Allows security actions for SiteIdentityPermission to be applied to code using declarative security. This class cannot be inherited.
public string Site { get; set; }

Gets or sets the site name of the calling code.

public SiteIdentityPermissionAttribute(SecurityAction action)

Initializes a new instance of the SiteIdentityPermissionAttribute class with the specified SecurityAction.