Cloudflare blocked a DDoS attack that lasted a month and peaked at 3.8 terabits per second: a world record.

For a month, cybercriminals attempted to paralyze services and websites from the financial, telecommunications and internet industries with a DDoS attack. To do this, they collected malicious traffic that peaked at 3.8 terabits per second. This makes the DDoS attack the largest attack observed to date.

Cloudflare blocked the attack and collected data about its nature. The criminals used cracked devices worldwide to send the malicious packets for the DDoS attack, but the focus was in Russia and the USA. There was also a lot of traffic coming from Spain.

Poorly secured routers

The botnet behind the attack consisted mainly of (IoT) devices. Think, for example, of cracked routers from Asus and Miktrotik, DVRs and web servers. This once again shows the danger of poorly secured small devices on the Internet. Manufacturers and end users do not always take the security of such devices seriously enough, allowing criminals to exploit them to harm third parties.

In this case, Cloudflare was able to block the attack on its own. The company reports that the peak of the DDoS block lasted about 65 seconds. The world’s strongest attack to date was blocked by Microsoft and targeted the Azure network. It had a magnitude of 3.47 terabits per second.