It looks like there have been breaking changes at the malware domain list feed. The URL http://www.malwaredomainlist.com/updatescsv.php returns an empty text, therefore parsing fails.

The website doesn't show any current information. Maybe the feed has been discontinued?

Does anyone know if http://www.malwaredomainlist.com/ is still active? I haven't yet discovered any discontinuation notice on the webpage and the forum. If the feed stopped, we can remove the feed and parser completely, otherwise we should fix the parser to handle that

I don't know precisely when it might have stopped working, but we noticed no new data arriving in late 2019 and the Wayback Machine suggests it stopped updating well before that.

Chris