incorrect link on image on media attachment pages

I have tried to search for the answer but am challenged to know what search words to use. I have also stared at various pages about attachments on the wordpress codex but my grasp of PHP is not quite up to understanding what is written there.

On any media attachment page on my site, the link on the featured image is pointing to the wrong image – it links to the next media attachment page in the images associated with that particular post.

An example (purposely unlinked, to prevent undue spamming of my site) for the post “wordless-glass-is-greener”, the media attachment page begins here: etherwork[dot]net/blog/wordless-glass-is-greener/3278nffttapples800x650/

Where in WordPress admin do I go to either remove the link on the image entirely – that would be ideal – or change the link to go to the image itself?

I’m guessing that this is controlled in wp-includes/media.php but have no idea how to do a rewrite (if that is what is needed) for the functions file in my theme folder.

I hope my question made sense. Thank you for any help you can offer.

E Morris, using a child theme of twenty twelve

I do not at all understand what is written here:
https://codex.www.ads-software.com/Function_Reference/the_attachment_link