Microsoft claimed to have thwarted what it dubbed the largest DDoS attack ever observed in the cloud.

The exploit measured at 15.72 Tb/s and 3.64 billion packets per second (pps), targeting a single Australia-based endpoint.

“The attack involved extremely high-rate UDP floods targeting a specific public IP address, launched from over 500,000 source IPs across various regions. These sudden UDP bursts had minimal source spoofing and used random source ports, which helped simplify traceback and facilitated provider enforcement,” explained Sean Whalen, senior product marketing manager for Azure Platform Security.

Detected and mitigated by Azure DDoS Protection, the attempt was pinned down to Aisuru, a Turbo Mirai-class botnet that targets internet of things (IoT) flaws, mainly in the form of home routers and cameras.

Whalen warned businesses to make sure their internet-facing applications and workloads are sufficiently protected against DDoS attacks, and to conduct regular simulations to discover and address potential issues proactively.

The Aisruru attack follows other high-profile DDoS exploits, such as a 22.2 Tb/s attempt which Cloudflare prevented in September.

In a recent report from Nexusguard, the total number of DDoS attacks was revealed to have increased by just 2% year-over-year (YoY) – but the average attack size increased by 69%, with maximum attack sizes reaching 962.2 Gb/s in scale.

A telecom-focused security report from Nokia, meanwhile, reported 52% of DDoS attacks hit multiple hosts simultaneously, with 58% using multiple vectors, and 78% finishing within five minutes.

Nokia said this “new wave of ‘terabit tsunami’ attacks” is testing the limits of traditional defenses, requiring operators to start adopting AI-driven DoS defenses.

“Legacy methods like blackholing or traffic scrubbing simply can’t keep up with the scale and sophistication of modern threats. The path forward lies in solutions that blend speed, intelligence, and scale, powered by AI, to help operators stay several steps ahead in an increasingly volatile threat environment,” a Nokia spokesperson told SDxCentral by email.