It has happened twice now on two different banks. These are e-statements: emailed PDF statements. I have reported the issue to both banks. Let’s see what they do.
It seems the issue is not new. Other customers with other banks have had it happen to them:
In my case, the banks have sent me password protected PDFs. When I could not open them, I got curious. I investigated it further, and that’s when I discovered what was going on. So, have you received an e-statement you could not open?