Cloudflare: World Record 7.3Tbps DDoS Attack Hits Mystery Target

Yahoo

22-06-2025

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The biggest recorded distributed denial-of-service (DDoS) attack in history was recorded on Friday, in what could be a concerning development for website owners everywhere.
DDoS attacks are one of the most prevalent types of cyberthreats. These attacks attempt to flood a website with traffic, often flowing from different IP addresses across the world, in the hopes that it will crash. These types of attacks have taken down everything from cloud storage giant Microsoft Azure, Elon Musk's X, to the Internet Archive in just the past few years alone.
Internet security firm Cloudflare says it stopped a 45-second-long DDoS attack that peaked at 7.3 terabits per second, translating to a total of roughly 37.4 terabytes of data. To put this in perspective, that's about 375 modern AAA video games, which can weigh in at 100GB each, or up to 311 days of 1080p HD video. It's also equivalent to around 9.35 million songs stored as MP3s.
Cloudflare didn't reveal the victim of Friday's attack, other than that it was a Cloudflare customer—like most major high-traffic websites on the internet—which doesn't narrow it down a great deal. Cloudflare says the attack is what it termed a "multivector DDoS attack," but said that 99.996% of the malicious attack traffic was executed via what is known as "UDP floods."
UDP is a way of routing internet traffic used in instances where fast responses are needed, such as online gaming or Zoom calls, in contrast to TCP, which is used for the majority of online traffic.
The internet security firm says the attack originated from over 122,145 source IP addresses across 161 countries. Almost half of the attack traffic came from Brazil and Vietnam, with roughly a quarter each. Another third originated from Taiwan, China, Indonesia, Ukraine, Ecuador, Thailand, the United States, and Saudi Arabia.
It will be interesting to see how long the current record may stand—Cloudflare has reported several record-breaking DDoS attacks over the past year. In late January 2025, Cloudflare warded off a 5.6Tbps attack, a record at the time, just months after fending off a 4.2Tbps attack. Meanwhile, tech giants like Microsoft are warning how DDoS attacks may be used offensively by technologically advanced foreign powers like Iran, North Korea, or Russia.