The Federal Bureau of Investigation (FBI) said today it worked with industry partners to seize hundreds of domains associated with NetNut, a sprawling residential proxy service operated by the publicly-traded Israeli company Alarum Technologies [NASDAQ: ALAR]. The action comes roughly two weeks after KrebsOnSecurity published findings from multiple security firms connecting NetNut to the Popa botnet, a collection of at least two million devices that have been compromised by malicious software with little or no consent from victims.

The NetNut homepage today was replaced by this seizure banner from the FBI.

On June 19, three different security firms issued similar findings: That NetNut is a residential proxy network which populates a botnet called Popa, and distributes software for devices commonly found in homes, such as smart TVs and streaming boxes. NetNut’s software turns those systems into always-on residential proxy nodes that are rented to others, who predominantly use them to relay abusive and intrusive Internet traffic, such as mass content scraping, advertising fraud, and account takeover activity.

Earlier today, NetNut’s homepage was replaced with a seizure notice from the FBI and the Internal Revenue Service Criminal Investigation division. The seizure notice thanked Google, Lumen, Shadowserver and other industry partners for their help in dismantling hundreds of domains tied to the Popa botnet, which experts say has long been synonymous with NetNut’s residential proxy infrastructure.

In a blog post published today, the Google Threat Intelligence Group (GTIG) said NetNut’s proxy network is widely resold and white-labeled by a number of third-party proxy providers, and that its services are heavily sought out by cybercriminals seeking to obfuscate the source of their malicious traffic. The GTIG said that in a single week during June 2026, they observed 316 distinct clusters of threat actors using suspected NetNut exit nodes, including cybercriminal and espionage groups.

“These bad actors can use NetNut to mask their origin IP address when accessing victim environments, accessing their own infrastructure, and conducting password spray attacks,” Google’s GTIG wrote. “Furthermore, when a consumer device becomes an exit node, unauthorized network traffic passes through it. This means bad actors can access other private devices on the same home network, effectively exposing them to Internet threats.”

Google said it disabled Google accounts and services used by NetNut for malware command and control, and that it shared technical intelligence on NetNut’s software development kits (SDKs) and backend infrastructure with platform providers, law enforcement and research firms. The company also disabled apps known to bundle NetNut’s various SDKs.

Omer Weiss, legal counsel for NetNut parent Alarum Technologies, said the company was aware of the FBI seizure and cooperating with investigators.

“Alarum takes this matter seriously and will fully cooperate with law enforcement to ensure any misuse of its infrastructure is thoroughly investigated and those responsible are held to account,” Weiss said in a written statement.

Benjamin Brundage is founder of the proxy tracking service Synthient, one of the companies that published evidence last month linking the Popa botnet to NetNut and Alarum Technologies. Brundage said the domain seizures appear to have disrupted both the Popa botnet and the NetNut proxy network that rides on top of it.

Brundage said NetNut’s apparent demise is likely to be a great disadvantage for the cybercrime community, which was already reeling from legal actions by Google earlier this year that seized infrastructure for NetNut’s biggest competitor — IPIDEA.

“I think this takedown is going to have a big impact, because NetNut gained significant popularity after the IPIDEA takedown,” he said. “Also NetNut has been incredibly common among resellers, and they were on par with IPIDEA in terms of their daily traffic, quality, size, price per gigabyte, all of it.”

NetNut’s infrastructure, in a nutshell. Image: Black Lotus Labs, Lumen.

The NetNut and Popa botnet takedown may have another added benefit, Brundage said: Lessening the impact of large distributed denial-of-service botnets that have been built on the backs of poorly configured residential proxy services. In January, Synthient revealed how cybercriminals had built the world’s largest DDoS botnet (Kimwolf) by tunneling through IPIDEA proxy connections into the local networks of TV box owners, and infecting other Android-based devices behind the victim’s firewall.

While many of the bigger proxy providers took steps to block this activity, resellers of the major proxy networks have been far slower to respond to the threat, Brundage said.

“In terms of all these TV box devices getting compromised from the proxy network, it will have an impact on the DDoS botnets out there,” he said.

For its part, Google reckons today’s actions have caused “significant degradation to NetNut’s proxy network and its business operations, reducing the available pool of devices for the proxy operator by millions.” But the company warns that proxy networks can rebuild themselves by effectively reselling other proxy services, as IPIDEA has done over the past few months.

“Google has high confidence that many popular residential proxy brands are in fact whitelabeling the NetNut botnet,” the GTIG report concludes. “While we expect this disruption to have a larger ripple effect across the residential proxy ecosystem, observations after the disruption of IPIDEA proved that individual networks can appear resilient. What we have observed is that when faced with the degradation of their own botnet, proxy operators begin buying capacity from their competitors, effectively becoming a reseller. We recognize that creating a lasting disruption in this fluid ecosystem means we must scale our efforts to target the infrastructure of several interconnected providers.”

As KrebsOnSecurity has warned repeatedly, most of the no-name TV streaming boxes for sale on the major e-commerce websites either come pre-installed with residential proxy software, or require the installation of proxy SDKs in order to use the device for its stated purpose (streaming pirated movies, sporting events and TV shows). Google’s advice here is sound: When it comes to TV boxes, stick to name brands from reputable manufacturers, and then be sparing and judicious with any apps you choose to install.

The sketchy TV boxes that are being commandeered by the Popa botnet and other threats all come with or require the user to install unofficial Android operating systems that do not operate within the confines of Google’s Official Play Protect store. Google says consumers can confirm whether or not a device is built with the official Android TV OS and Play Protect certification by following these instructions.

Even people without TV streaming boxes can find their smart TVs enrolled in residential proxy networks, just by installing one of thousands of apps available for download on Samsung and LG smart TVs. In a report released last month, the proxy tracking company Spur found 42 percent of apps available for download via the webOS operating system on LG smart TVs include SDKs that turn one’s television into an always-on residential proxy node. More than a quarter of the apps made for Samsung’s Tizen operating system had similar residential proxy components, Spur found.

Image: Spur.us.

Update, 4:24 p.m. ET: Included a statement shared post-publication from an attorney representing NetNut parent Alarum Technologies.

Update, July 8, 2:34 p.m. ET: The website for Alarum Technologies — alarum[.]io — now also features a seizure notice from the FBI. The company’s stock has taken a beating since the FBI action, and is currently trading at $2.62 a share, a roughly 67 percent decline over the past week.

Hackers linked to Russia’s military intelligence units are using known flaws in older Internet routers to mass harvest authentication tokens from Microsoft Office users, security experts warned today. The spying campaign allowed state-backed Russian hackers to quietly siphon authentication tokens from users on more than 18,000 networks without deploying any malicious software or code.

Microsoft said in a blog post today it identified more than 200 organizations and 5,000 consumer devices that were caught up in a stealthy but remarkably simple spying network built by a Russia-backed threat actor known as “Forest Blizzard.”

How targeted DNS requests were redirected at the router. Image: Black Lotus Labs.

Also known as APT28 and Fancy Bear, Forest Blizzard is attributed to the military intelligence units within Russia’s General Staff Main Intelligence Directorate (GRU). APT 28 famously compromised the Hillary Clinton campaign, the Democratic National Committee, and the Democratic Congressional Campaign Committee in 2016 in an attempt to interfere with the U.S. presidential election.

Researchers at Black Lotus Labs, a security division of the Internet backbone provider Lumen, found that at the peak of its activity in December 2025, Forest Blizzard’s surveillance dragnet ensnared more than 18,000 Internet routers that were mostly unsupported, end-of-life routers, or else far behind on security updates. A new report from Lumen says the hackers primarily targeted government agencies—including ministries of foreign affairs, law enforcement, and third-party email providers.

Black Lotus Security Engineer Ryan English said the GRU hackers did not need to install malware on the targeted routers, which were mainly older Mikrotik and TP-Link devices marketed to the Small Office/Home Office (SOHO) market. Instead, they used known vulnerabilities to modify the Domain Name System (DNS) settings of the routers to include DNS servers controlled by the hackers.

As the U.K.’s National Cyber Security Centre (NCSC) notes in a new advisory detailing how Russian cyber actors have been compromising routers, DNS is what allows individuals to reach websites by typing familiar addresses, instead of associated IP addresses. In a DNS hijacking attack, bad actors interfere with this process to covertly send users to malicious websites designed to steal login details or other sensitive information.

English said the routers attacked by Forest Blizzard were reconfigured to use DNS servers that pointed to a handful of virtual private servers controlled by the attackers. Importantly, the attackers could then propagate their malicious DNS settings to all users on the local network, and from that point forward intercept any OAuth authentication tokens transmitted by those users.

DNS hijacking through router compromise. Image: Microsoft.

Because those tokens are typically transmitted only after the user has successfully logged in and gone through multi-factor authentication, the attackers could gain direct access to victim accounts without ever having to phish each user’s credentials and/or one-time codes.

“Everyone is looking for some sophisticated malware to drop something on your mobile devices or something,” English said. “These guys didn’t use malware. They did this in an old-school, graybeard way that isn’t really sexy but it gets the job done.”

Microsoft refers to the Forest Blizzard activity as using DNS hijacking “to support post-compromise adversary-in-the-middle (AiTM) attacks on Transport Layer Security (TLS) connections against Microsoft Outlook on the web domains.” The software giant said while targeting SOHO devices isn’t a new tactic, this is the first time Microsoft has seen Forest Blizzard using “DNS hijacking at scale to support AiTM of TLS connections after exploiting edge devices.”

Black Lotus Labs engineer Danny Adamitis said it will be interesting to see how Forest Blizzard reacts to today’s flurry of attention to their espionage operation, noting that the group immediately switched up its tactics in response to a similar NCSC report (PDF) in August 2025. At the time, Forest Blizzard was using malware to control a far more targeted and smaller group of compromised routers. But Adamitis said the day after the NCSC report, the group quickly ditched the malware approach in favor of mass-altering the DNS settings on thousands of vulnerable routers.

“Before the last NCSC report came out they used this capability in very limited instances,” Adamitis told KrebsOnSecurity. “After the report was released they implemented the capability in a more systemic fashion and used it to target everything that was vulnerable.”

TP-Link was among the router makers facing a complete ban in the United States. But on March 23, the U.S. Federal Communications Commission (FCC) took a much broader approach, announcing it would no longer certify consumer-grade Internet routers that are produced outside of the United States.

The FCC warned that foreign-made routers had become an untenable national security threat, and that poorly-secured routers present “a severe cybersecurity risk that could be leveraged to immediately and severely disrupt U.S. critical infrastructure and directly harm U.S. persons.”

Experts have countered that few new consumer-grade routers would be available for purchase under this new FCC policy (besides maybe Musk’s Starlink satellite Internet routers, which are produced in Texas). The FCC says router makers can apply for a special “conditional approval” from the Department of War or Department of Homeland Security, and that the new policy does not affect any previously-purchased consumer-grade routers.