I’ve been getting the same thing for the past few weeks 🙁
Just found http://ocaoimh.ie/did-your-wordpress-site-get-hacked/ today, might help find where they are installing backdoors.
If PHP is trying to read past the end of a file it is most likely an open bracket (like {) that isn’t matched up with a closing bracket (like }).
If you use something like notepad++ it will show matching pairs of brackets, download that (or something similar) and put } at the end of the file and if it matches something it will show it and you can see where you have a bracket that is not being closed.
Or just put } just before the ?> at the end of the file and see if it clears it up.
I think you need to have text as well as an image in the link for it to work. It’s working fine for me with V2.8.3