So i had this issue in the pass. These links pop up in two ways from what i think i learned. your direct url or anchor texted to the page or a compeititor or person decided to redirect multiple sites to your website to lower your positions. I was redirected to on multiple sites.
In my case I do not know the exact effect but the page that was under attack ranked in first place as long as it was under attack. So I asked a ton of questions and kind of did nothing.
You can alway ask google. I did nothing because it help me but just guessing you want to watch who is linking to you or giving you links so you dont get in trouble. I have no clue how they know if you got spammed, bought back links or redirected too.
Sorry for clear unclear answer.