We use PDFs for all our common sharing, white papers, publications, contracts etc. You may have heard that these can be paths to infections but now this is becoming a greater threat. The threat comes from recent nation states ramping up the numbers and the places that infections come from. They’ll take even well known existing PDFs and refactor them to be sources of infections.
The bottom line is be cautious of PDF downloading and reading and just reduce the number to those that are absolutely necessary.