According to BleepingComputer, content delivery network Cloudflare recently recorded the largest distributed denial-of-service (DDoS) attack ever measured. As of September 2025, Cloudflare is used by approximately 19.8 percent of all websites as a reverse proxy.
At its peak, the enormous DDoS attack measured a whopping 22.2 terabits per second (TB/s) of network activity, blowing out of the water the previous record of 11.5 TB/s from three weeks ago.
The DDoS attack lasted 40 seconds and was equivalent to streaming 1 million 4K videos simultaneously:
Despite the short assault period, the volume of traffic directed at the victim was enormous, roughly equivalent to streaming one million 4K videos simultaneously.
The packet rate of 10.6 Bpps can be translated to roughly 1.3 web page refreshes per second from every person on the planet.
The large volume of packets makes it particularly difficult for firewalls, routers, and load balancers to process the requests, even if the total bandwidth is manageable.
It’s yet unclear who was behind the record-breaking DDoS attack, but experts say the previous one was carried out by a botnet called Aisuru.
This article originally appeared on our sister publication PC för Alla and was translated and localized from Swedish.
