There are some here, as test files in the qpdf library: https://github.com/qpdf/qpdf/tree/main/qpdf/qtest/qpdf https://github.com/qpdf/qpdf/tree/main/qpdf/qtest

There are some here, as test files in the qpdf library: https://github.com/qpdf/qpdf/tree/main/qpdf/qtest/qpdf https://github.com/qpdf/qpdf/tree/main/qpdf/qtest/qpdf (But still, note: A couple of months ago I wrote a low-level PDF parser—just parse the PDF file's bytes into PDF objects, nothing more—and fed it all the PDF files that happened to be present on my laptop, and ran into some files that (some) PDF viewers open, but even qpdf doesn't. I say "even" because qpdf is really good IMO.)