Authorities arrested and unsealed charges against a Canadian man accused of running Kimwolf, one of the most far-reaching DDoS botnets on record, the Justice Department said Thursday.

Jacob Butler was arrested Wednesday in Ottawa, Canada, and awaits extradition to the United States where he is charged with aiding and abetting computer intrusions and, if convicted, faces up to 10 years in prison.

Investigators said the 23-year-old, also known as “Dort,” was a principal administrator of Kimwolf, a variant of the record-setting Aisuru DDoS botnet that spread like wildfire and eventually took over more than 2 million Android TV devices after its operators figured out how to abuse residential-proxy networks for local control.

Authorities in March seized infrastructure powering the Kimwolf, Aisuru, JackSkid and Mossad botnets, which hijacked a combined three million devices and launched more than 300,000 DDoS attacks collectively.

Kimwolf, which operated as a DDoS-for-hire service for other cybercriminals, initiated more than 25,000 attacks, resulting in network outages, disruptions and financial losses exceeding millions of dollars, officials said. Officials also said they found evidence linking Kimwolf to DDoS attacks targeting Department of Defense Information Network IP addresses.

“Kimwolf and the botnets associated with this operation have supported persistent corporate intrusion efforts and been used by a wide range of serious threat actors,” Zach Edwards, staff threat researcher at Infoblox, told CyberScoop.

Authorities searched Butler’s residence during the globally coordinated operation, but did not arrest him until Wednesday, roughly two months later. Officials filed a criminal complaint against Butler in the U.S. District Court for the District of Alaska in April, and unsealed the complaint following his arrest.

A special agent with the Defense Criminal Investigative Service confirmed Butler’s identity and involvement in the Kimwolf botnet after Butler used the same IP address to access multiple email accounts he controlled and Discord accounts linked to Kimwolf. 

“I have observed significant operational security lapses on Butler’s part resulting in patterns of overlapping IP usage among a Google account in Butler’s true name, other Google accounts that I believe to be controlled by Butler due to use of the same machine cookies, and Discord accounts which have been used in support of the KimWolf operation,” the special agent said in an affidavit. 

“The Discord accounts show patterns of overlapping IP usage with the KimWolf backend server. These IP addresses appear to be proxy or VPN IPs which were likely used by Butler in an unsuccessful attempt to evade law enforcement scrutiny. However, like many cybercriminals, Butler did not use proxy or VPN IP addresses exclusively,” the special agent added. 

Authorities described the botnet takedowns in March in nearly conclusive terms at the time, yet court records indicate the Kimwolf botnet is back in operation. 

“While today’s announcement is encouraging to see, there are still hundreds of millions of insecure IoT and network devices connected to sensitive government, corporate and home networks, and these remain a priority target for threat actors looking to build the next version of Kimwolf,” Edwards said.

“Until we find solutions to this underlying problem,” he added, “we’ll unfortunately continue to play Whac-A-Mole with botnet operators year after year.”

You can read the affidavit supporting the criminal complaint against Butler below.

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Canadian authorities on Wednesday arrested a 23-year-old Ottawa man on suspicion of building and operating Kimwolf, a fast spreading Internet-of-Things botnet that enslaved millions of devices for use in a series of massive distributed denial-of-service (DDoS) attacks over the past six months. KrebsOnSecurity publicly named the suspect in February 2026 after the accused launched a volley of DDoS, doxing and swatting campaigns against this author and a security researcher. He now faces criminal hacking charges in both Canada and the United States.

A criminal complaint unsealed today in an Alaska district court charges Jacob Butler, a.k.a. “Dort,” of Ottawa, Canada with operating the Kimwolf DDoS botnet. A statement from the Department of Justice says the complaint against Butler was unsealed following the defendant’s arrest in Canada by the Ontario Provincial Police pursuant to a U.S. extradition warrant. Butler is currently in Canadian custody awaiting an initial court hearing scheduled for early next week.

The government said Kimwolf targeted infected devices which were traditionally “firewalled” from the rest of the internet, such as digital photo frames and web cameras. The infected systems were then rented to other cybercriminals, or forced to participate in record-smashing DDoS attacks, as well as assaults that affected Internet address ranges for the Department of Defense. Consequently, the DoD’s Defense Criminal Investigative Service is investigating the case, with assistance from the FBI field office in Anchorage.

“KimWolf was tied to DDoS attacks which were measured at nearly 30 Terabits per second, a record in recorded DDoS attack volume,” the Justice Department statement reads. “These attacks resulted in financial losses which, for some victims, exceeded one million dollars. The KimWolf botnet is alleged to have issued over 25,000 attack commands.”

On March 19, U.S. authorities joined international law enforcement partners in seizing the technical infrastructure for Kimwolf and three other large DDoS botnets — named Aisuru, JackSkid and Mossad — that were all competing for the same pool of vulnerable devices.

On February 28, KrebsOnSecurity identified Butler as the Kimwolf botmaster after digging through his various email addresses, registrations on the cybercrime forums, and posts to public Telegram and Discord servers. However, Dort continued to threaten and harass researchers who helped track down his real-life identity and dramatically slow the spread of his botnet.

Dort claimed responsibility for at least two swatting attacks targeting the founder of Synthient, a security startup that helped to secure a widespread critical security weakness that Kimwolf was using to spread faster and more effectively than any other IoT botnet out there. Synthient was among many technology companies thanked by the Justice Department today, and Synthient’s founder Ben Brundage told KrebsOnSecurity he’s relieved Butler is in custody.

“Hopefully this will end the harassment,” Brundage said.

The government says investigators connected Butler to the administration of the KimWolf botnet through IP address, online account information, transaction records, and online messaging application records obtained through the issuance of legal process. The criminal complaint against Butler (PDF) shows he did little to separate his real-life and cybercriminal identities (something we demonstrated in our February unmasking of Dort).

In April, the Justice Department joined authorities across Europe in seizing domain names tied to nearly four-dozen DDoS-for-hire services, although because of a bureaucratic mix-up the list of seized domains has remain sealed until today. The DOJ said at least one of those services collaborated with Butler’s Kimwolf botnet.

A statement from the Ontario Provincial Police said a search warrant was executed on March 19 at Butler’s address in Ottawa, where they seized multiple devices. As a result of that investigation, Butler was arrested and charged this week with unauthorized user of computer; possession of device to obtain unauthorized use of computer system or to commit mischief; and mischief in relation to computer data. He is scheduled to remain in custody until a hearing on May 26.

In the United States, Butler is facing one count of aiding and abetting computer intrusion. If extradited, tried and convicted in a U.S. court, Butler could face up to 10 years in prison, although that maximum sentence would likely be heavily tempered by considerations in the U.S. Sentencing Guidelines, which make allowances for mitigating factors such as youth, lack of criminal history and level of cooperation with investigators.

Authorities seized infrastructure powering four botnets that hijacked a combined three million devices and launched more than 300,000 DDoS attacks collectively, the Justice Department said Thursday.

The botnets — Aisuru, Kimwolf, JackSkid and Mossad — enabled operators to sell access to the infected devices for various cybercrimes. The aftermath spanned thousands of attacks, including some demanding extortion payments from victims, officials said.

The globally coordinated operation, aided by law enforcement actions targeting the botnets’ operators in Canada and Germany, disrupted the command-and-control infrastructure for all four botnets. Two of the botnets set records before the takedown, attracting widespread attention from security researchers and vendors.

The Kimwolf botnet, an Android variant of Aisuru, spread like wildfire after its operators figured out how to abuse residential-proxy networks for local control, according to Sythient. It eventually took over more than 2 million Android TV devices by January. In September, just as Kimwolf was forming, Cloudflare clocked the Aisuru botnet hitting a record-breaking 29.7 terabits-per-second DDoS attack that lasted 69 seconds.

Officials ultimately attributed roughly 200,000 DDoS attacks to Aisuru, 90,000 to JackSkid, 25,000 to Kimwolf and about 1,000 DDoS attack commands to the Mossad botnet. Yet, DDoS attacks from financially-motivated attackers are typically a distraction or misdirection.

“Oftentimes a DDoS attack is just advertising for the size of an operator’s botnet,” Zach Edwards, staff threat researcher at Infoblox, told CyberScoop. Botnet operators cash out by renting these controlled devices to cybercriminals for account abuse, password reset attacks, ad fraud schemes and residential proxy nodes, he added.

Devices infected by the four botnets include digital video recorders, web cameras, Wi-Fi routers and TV boxes. Hundreds of thousands of these devices are located in the United States, federal prosecutors said. 

Authorities did not name the people involved or formally announce any arrests. Yet, they describe the operation in nearly conclusive terms, claiming the action disrupted the botnets’ communications infrastructure — domains, virtual servers and other systems — to prevent further infection and limit or eliminate the botnets’ ability to launch future attacks.

“Cybercriminals infiltrate infrastructure beyond physical borders and Defense Criminal Investigative Service participates in international operations to help safeguard the Department’s global footprint,” Kenneth DeChellis, special agent in charge at the Defense Department’s DCIS cyber field office, said in a statement. Some of the DDoS attacks attributed to these botnets reached IP’s owned by the Department of Defense Information Network.

Botnets often compete for devices to infect and opportunities to scale. As Kimwolf spread and hit those objectives, it captured sweeping interest from researchers, authorities and vendors in a position to help stop it. 

Kimwolf was the largest DDoS botnet ever detected, according to Tom Scholl, vice president at Amazon Web Services, which assisted the operation. “The scale of this botnet is staggering,” he said in a LinkedIn post. 

“Kimwolf represented a fundamental shift in how botnets operate and scale,” Scholl added. “Unlike traditional botnets that scan the open internet for vulnerable devices, Kimwolf exploited a novel attack vector: residential proxy networks.”

Under this mechanism, any organization with vulnerable devices connected to the internet could unwittingly have those devices turned into a node for a botnet or a foothold for a targeted attack.

“This isn’t just some problem that your cousin has because he bought some cheap TV box that promised him free TV channels,” Edwards said. Infoblox previously said nearly 25% of customers had at least one endpoint device in a residential proxy service targeted by Kimwolf.

While it’s intellectually interesting whenever a botnet scales to extraordinary size, it’s also a “sad reminder that oftentimes security takes a back seat to convenience and cost,” Edwards said. 

“The botnets are growing because more and more people are buying weird internet-connected stuff,” he added. “Nothing in this world is free.”

The takedowns mark a continuation of a consistent, ongoing crackdown targeting large-scale botnets, cybercrime marketplaces, malware, infostealers and other cybercrime tools. Some of the malicious networks hampered or rendered nonoperational by disruptions and arrests during the past year include: DanaBot, Rapper Bot, Lumma Stealer, AVCheck and SocksEscort.

More than 20 companies and organizations assisted with the coordinated disruption, including law enforcement from the Netherlands and Europol. Efforts to stop botnets will continue as these malicious networks proliferate in new places and new ways. 

“We’re living in a device-compromise–DDOS-botnet-merry-go-round and while many of us wish something could slow it down, the challenges continue to grow,” Edwards said. “This is still a bad day for serious threat actors, and any day like that is something we should all celebrate.”

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