Microsoft successfully blocked a 2.4 Tbps Distributed Denial of Service (DDoS) attack on one of its European Azure cloud customers.
Distributed Denial of Service (DDoS) attacks are happening ever more often and growing ever bigger. At 2.4 terabits per second (Tbps), the DDoS attack Microsoft just successfully defended European Azure cloud users against could be the biggest one to date. What we know for certain is it’s the biggest DDoS attack on an Azure cloud customer. It was bigger than the previous high,2020’s Azure 1 Tbps attack, and Microsoft reported it was „higher than any network volumetric event previously detected on Azure.“ Who was targeted? We don’t know. Microsoft isn’t talking. The attack itself came from over 70,000 sources. It was orchestrated from multiple Asia-Pacific countries such as Malaysia, Vietnam, Taiwan, Japan, and China, and from the United States. The attack vector was a User Datagram Protocol (UDP) reflection attack. The attack lasted over 10 minutes with very short-lived bursts. Each of these bursts ramped up in seconds to terabit volumes. In total, Microsoft saw three main peaks, the first at 2.4 Tbps, the second at 0.55 Tbps, and the third at 1.7 Tbps. In a UDP reflection attack, the attacker exploits the fact that UDP is a stateless protocol. That means the attackers can create a valid UDP request packet listing the attack target’s IP address as the UDP source IP address.
