WordPress 4.9 Hyperlink Image issue

Hello there,

I just upgraded to WordPress version 4.9 and am now some of the images pulled from hyperlinks are showing incorrectly. The image is now the width of the page and blurry.

Please see https://writerswrite.co.za/book-review-how-to-stop-time/, the image for How to Stop Time, buy now at raru.co.za is huge. The url for that image is https://raru.co.za/rafa75e87/books/5511477-how-to-stop-time-matt-haig-hardcover.

Thank you for all of your help.

Regards,
Blair

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