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October 15, 2021

Microsoft toned down one of the largest DDoS attacks ever

The attack was 2.4 Tbps

Microsoft says it was able to mitigate a 2.4 Tbps Distributed Denial-of-Service (DDoS) attack in August. The attack targeted an Azure customer in Europe and was 140 percent higher than the highest attack bandwidth volume recorded by Microsoft in 2020. It also exceeds last year’s peak traffic volume of 2.3 Tbps targeting Amazon Web Services, although it was a smaller attack than the attack. 2.54 Tbps one that Google reduced in 2017.

Microsoft says the attack lasted more than 10 minutes, with transient bursts of traffic peaking at 2.4 Tbps, 0.55 Tbps, and finally 1.7 Tbps. DDoS attacks are usually used to force websites or services offline, thanks to a flow of traffic that a web host cannot handle. They are usually run through a botnet, a network of machines compromised with malware or malicious software to control them remotely. Azure was able to stay online during the attack, thanks to its ability to absorb dozens of terabits of DDoS attacks.

Inbound UDP attack bandwidth mitigated (Tbps)
The attack on Azure lasted more than 10 minutes. Image: Microsoft

“The attack traffic came from approximately 70,000 sources and from multiple countries in the Asia-Pacific region, such as Malaysia, Vietnam, Taiwan, Japan and China, as well as from the United States,” explains Amir Dahan, senior program manager . for Microsoft’s Azure networking team.

While the number of DDoS attacks on Azure has increased in 2021, the maximum attack throughput had fallen to 625 Mbps before this 2.4 Tbps attack in the last week of August. Microsoft does not name the target Azure customer in Europe, but such attacks can also be used as a cover for secondary attacks that attempt to spread malware and infiltrate corporate systems.

The attack is one of the largest in recent history. Last year, Google released a 2.54 Tbps DDoS attack described it softening in 2017, and Amazon Web Services (AWS) mitigated a 2.3 Tbps attack. In 2018, NetScout Arbor repelled a 1.7 Tbps attack.

Source: TheVerge

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