The PDFs with the MD5 Hash-verified OS X Malware come from OS X Malware Testers.
The MD5 Hash-verified OS X Malware has been approved by
the Malware Analysts of the OS X Security software Vendors, too.
Since you are an OS X Malware Expert (I assume...),
you need to scientifically prove your claim that
'OS X is Malware-impenetrable.'
1. Come in contact with both OS X Malware Testers and
Malware Analysts of the OS X Security software Vendors.
2. Ask the OS X Malware Samples from them.
3. Setup your OS X Malware Tests.
4. Conduct your Tests.
5. Record your Test Results proving that 'OS X is Malware-impenetrable.'
6. Publish your Test Results in the OS X Community.
Sorry, but I haven't seen such a thing up to now...
[Due to Fairness and Objectivity, I hope my post will survive this time...
Especially when someone ALWAYS challenges by using Bold-type]