Weird (spammy) websites creating backlinks to my images should I disavow ?

Hi,
Since about a month some weird websites started creating backlink to my images
To name a few because there are 50+
https://backdoor.spb.ru/http://fiberpkg.com/http://pixxel18studios.com/
The page linking to my website is always named after one of my KW like:
http://fiberpkg.com/MY_KEYWORK.html
The links are detected by Semrush but when I inspect the page source I can't find anything related to my website. Allegedly the anchor (of the image so I guess the alt property ?) is something like this:
"random_keyword1 random_keyword2 random_keyword3 random_keyword4 MY_KEYWORD"

I checked, one of my competitors has the same thing happening to his website.

What is the best course of action for this ? Are they 100% bad ? Should I prevent external domains from linking to my images ?
What would be the pros and cons of disavowing ?
What do you think is the goal of those websites ? Are they randomly generating content just for the sake of generating content or are they doing it to lower my ranking ?

Thanks for your help

Dissavvowing is soooo 2018. There is a reason in GSC it is already not directly accessible anymore through the menu. The media on our website is being backlinked on a daily base. Before we had complete automated process in place to create disavvow list to upload to GSC and replace the image with a public NASA image of > 100MB. Ever since Google is "smart" enough to recognize this negative SEO we don't look into it anymore and disabled all.