Privilege to upload attachment

Summary:

Privilege to upload attachment

Content (please ensure you mask any confidential information):

We are configuring access when procurement contracts is assigned for users to review.
We would like to know the privilege that control addition of attachment in the document section.
Currently, we have made all other fields read only, but we want to make sure in attachment section addition of attachment should be enabled.

Version (include the version you are using, if applicable):

24B

Code Snippet (add any code snippets that support your topic, if applicable):