Malware Activity in Hosting Networks (ASNs) April 1,2025 - June 30,2025

To see where malware was being served up, or distributed among peer-to-peer hosts, we collected the IP addresses that malware domains and malware URLs were resolving to when malware activity was reported. We then identified the Autonomous System (ASN) where the IP prefix containing the IP address to identify the hosting network where malware were reported.

IPv4 addresses may be reported for hosting one or more malware; for example, two or several URLs may contain the same IPv4 address but the PATHS or QUERIES may identify different malware.

In the table below, we show the twenty hosting networks with the highest numbers of IPv4 addresses reported as serving up or distributing malware (“Unique Malware Addresses”). Complete lists of ASNs where malware was reported for the quarter can be downloaded in CSV format from the Records page.