You can copy an attachment within a workflow into a resource with the advanced, utilities component: From attachment to a resource. The component has these parameters:
Attachment name
The name of the workflow attachment to copy.
Resource type
The resource type in the Library, that you want to copy the attachment to.
Resource path
The path and file name, that you want to copy the attachment to.
In the example above the attachment called: attachment.pdf is copied to the resource type, other in the subdirectory PDFs as the file/resource: Myfile.pdf.