I noticed that pages on my site would hang for a WHILE, so I did some investigation.

It turns out that the Adsterra JavaScript code was loading https://www.gatetodisplaycontent.com/7cb8fde86d9eb121ba106553cdc48d1a/invoke.js which would take more than a minute to finish (1.1 minutes according to the browser’s developer tools). It was a blocking call, so my site would not load while this script was executing.

Since breaking my site is unacceptable, Adsterra has been kicked out of the rotation.

That extremely long load time might also explain the terrible fill rate.

Bidvertiser served 3 times as many impressions on the same site over the same time period and did not prevent my site from loading.

I also noticed some weird behavior and could not easily figure out which script was causing it. Once in a while when I would click in a text box, a new tab would open to product.directredirection.com with a spammy malware site that was trying to trick me into installing a Chrome extension.

The URL:

The page:

More investigation revealed that Adsterra has been known to serve malvertising in the past:

https://blog.malwarebytes.com/cybercrime/2016/04/magnitude-ek-activity-at-its-highest-via-adsterra-malvertising/

https://searchsecurity.techtarget.com/news/252473229/Adsterra-still-connected-to-malvertising-campaign-despite-denials

I removed their JavaScript snippet and haven’t had that malware auto-navigation happen again.

Now it’s down to Bidvertiser, Galaksion, and RevenueHits.