Ability to add an attachment to a user defined form

Summary

Add PDF to user defined form

Content

We have a user defined form within transitions that when a candidate clicks on the e-offer, they are taken to the form to complete further details (date of birth and Ni Number) and also to esign the contract. We were wondering if we could add an attachment to this form so that we could say the candidate has successfully esigned the contract and the attached PDF. 

Currently we have a contents page displayed after the candidate fills out this form where they can pull of attachments, but there is a new legal requirement where we would need them to sign that they have seen and read an attached PDF. Is this possible?