In what security experts are calling the most powerful distributed denial-of-service (DDoS) attack ever recorded, a new IoT-based botnet dubbed “Aisuru” launched a 6.3 terabits-per-second digital assault—ten times the size of the infamous Mirai attack. The target: cybercrime journalist Brian Krebs. Though short-lived, the incident is being treated as a chilling demonstration of future cyberwarfare capabilities.
The Test Strike: 6.3 Tbps Against a Cybercrime Watchdog
In an unprecedented display of cyber firepower, security researcher and journalist Brian Krebs found himself once again on the frontlines of a digital battleground. On his widely followed blog KrebsOnSecurity, he revealed that a botnet called Aisuru unleashed a 6.3 terabits-per-second (Tbps) distributed denial-of-service (DDoS) attack—marking what experts believe is the largest botnet test strike ever recorded.
The attack lasted less than a minute but sent shockwaves across cybersecurity circles. According to Google security engineer Damian Menscher, whose team provides DDoS protection for Krebs’ site, this was the largest assault Google has ever mitigated.
“It was the type of attack normally designed to overwhelm network links,” Menscher stated. “For most companies, this size of attack would kill them.”
Krebs noted that the attack caused no visible disruption, largely due to its brevity and the robust mitigation in place. However, the nature and scale of the event point toward a much darker purpose: a test run to showcase the Aisuru botnet’s destructive capabilities to potential buyers.
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Botnets for Hire: IoT Devices and Telegram Deals
The term botnet refers to a collection of compromised internet-connected devices—often insecure IoT gadgets like smart fridges, door cameras, or thermostats—hijacked and controlled by hackers to flood targets with traffic. These attacks disrupt websites, overwhelm services, and increasingly serve as commoditized cyberweapons available for rent.
Aisuru was first spotted in cybercriminal forums last year offering DDoS-for-hire services at just $150 per day, though at that time it reportedly operated at one-third of its current strength. Since then, its sophistication and reach have expanded dramatically.
Cyber monitoring firm NetScout recently reported over 27,000 botnet attacks in March alone, with many orchestrated through Telegram groups, where criminal vendors auction off attack packages like subscription services. The Aisuru attack is believed to be a proof-of-concept strike, meant to attract high-paying clientele.
“This wasn’t random. It was a live advertisement,” one security analyst commented. “A flex of muscle in the underground marketplace.”
A Warning Shot for the Internet: What’s at Stake
The implications are sobering. Aisuru’s 6.3 Tbps capability dwarfs the 2016 Mirai botnet attack—then considered the gold standard of DDoS mayhem—which crippled large portions of the internet. Experts fear that Aisuru or its clonescould bring down major cloud providers, disrupt essential services, or be deployed in geopolitical conflicts.
What makes this more dangerous is the fragility of IoT ecosystems. These devices often ship with default credentials, lack security updates, and remain unmonitored by consumers. Each one is a potential soldier in an unseen army. Multiply that by millions of unsecured gadgets globally, and you get Aisuru.
Krebs, no stranger to botnet violence, emphasized the symbolic nature of the attack:
“DDoS attacks of such magnitude and brevity typically are produced when botnet operators wish to test or demonstrate their firepower for the benefit of potential buyers.”
With Aisuru now publicly proven, cybersecurity experts are urging enterprises, cloud providers, and governments to prepare for a new era of ultra-scale cyber threats—and to start treating IoT security as national infrastructure.