Also note that it's not necessarily safe to read these documents even if you don't intend on executing embedded code. For example, reading from pdfs uses poppler, which has had a few CVEs that could result in arbitrary code execution, mostly around image decoding. https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=poppler
(No shade to poppler intended, just the first tool on the list I looked at.)