Microsoft says it encountered the largest DDoS attack on record last November when a hacker tried to take down a customer’s online services.
The incident involved an unnamed customer in Asia, who uses Microsoft’s Azure cloud computing service. The hacker harnessed 10,000 computers across the globe, including in the US and China, to generate a massive 3.47Tbps DDoS attack, which lasted for 15 minutes.
The amount of traffic exceeds the 2.5Tbps assault Google fended off in 2017, which was the previous record holder for largest known DDoS attack.
Microsoft mentioned the 3.47Tbps attack in a report discussing its DDoS protection efforts through Azure. It’s unclear who instigated the assault and if it came from a hacker-controlled botnet. But the mysterious culprit used a variety of methods to amplify the DDoS attack, which included exploiting the UDP and CLDAP protocols in what’s known as “reflection attacks.”
In December, Microsoft also mitigated a series of other DDoS attacks targeting customers in Asia. The first peaked at 3.25Tbps, the second at 2.55Tbps. However, it seems the company defended against all the assaults without incident.
“In these cases, our customers do not have to worry about how to protect their workloads in Azure,” the company wrote in the report. “Azure’s DDoS protection platform, built on distributed DDoS detection and mitigation pipelines, can scale enormously to absorb the highest volume of DDoS attacks, providing our customers the level of protection they need.”
The company added that its DDoS protection services will continuously monitor a customer’s online services and scrub any bad traffic from the Azure network before it can disrupt services.
We’ve reached out to Microsoft for more details about the attacks, and we’ll update the story if we hear back. But the incident shows even the largest DDoS attacks can be foiled through protection services from the biggest cloud providers. Others, including Cloudflare and Amazon, have also touted fending off major DDoS assaults in recent years with relative ease.