Spamhaus Botnet threats: Most abused domain registrars, Q2 2021

Spamhaus: “After many years with no change at the top of the Spamhaus registrar reputation rankings, we finally have some movement!”.

Read here Spamhaus Botnet threats: Most abused top-level domains, Q2 2021


We saw an enormous 594% increase of newly registered botnet C&C domains at the US domain registrar NameSilo, knocking Namecheap off their #1 ranking. This was quite a feat considering that NameCheap saw a 52% increase in newly registered botnet C&C domains. These are huge numbers!

Germany and China

It was not only US-based registrars who saw significant increases in Q2. The two German-based domain registrars, Key Systems (56%) and 1API (254%), also experienced growth in the number of botnet domains registered through their services, as did almost all the Chinese registrars listed below, including eName Technology who entered our Top 20 at #3.

You can read the complete Spamhaus report here.

Download the Spamhaus Botnet Report 2021 Q2 as PDF


About Konstantinos Zournas

Studied Computer Engineering and Computer Science in London, UK and now living in Athens, Greece. Love domains and building websites. Went online in 1995, learned about HTML in 1996 and about domains in 2002. Started publishing the blog in 2012.

One comment

  1. Thanks, Konstantinos, I downloaded the report.


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