Your Smart Home Could Be Part of Someone Else's Cyberattack: What El Dorado Hills Homeowners Should Know

By Jon Yoffie | Yoffie Real Estate Group | Published June 15, 2026

In March 2026, law enforcement in the United States, Canada, and Germany seized the infrastructure behind four botnets that had quietly taken over more than 3 million home devices worldwide. Routers, security cameras, DVRs, streaming boxes. The kind sitting in homes across El Dorado Hills, Serrano, and Blackstone right now.

Two months earlier, in January 2026, a related botnet used 2 million hijacked home devices to launch the largest DDoS attack ever recorded at the time: 31 terabytes per second of traffic. Most of the homeowners whose devices were part of it never knew.

What's sitting on your home network right now, unpatched and forgotten, is part of a much bigger picture than most homeowners realize, and it matters if you're buying or selling a home with a smart system in El Dorado Hills, Serrano, or Blackstone. If that's where you are right now, talk to our team about what to check before you list or close.

How Do Smart Home Devices End Up in a Cyberattack?

Most of these devices aren't hacked one at a time. Criminal groups write malware that scans the internet for devices running outdated firmware or still set to factory-default logins, things like "admin" and "admin." Once a device is infected, it joins a network of millions of others, called a botnet, controlled remotely by whoever planted the malware.

The largest example uncovered so far is BADBOX 2.0, built mostly from cheap, uncertified streaming boxes and tablets. Investigators found malware pre-installed on more than 10 million devices before parts of it could be disrupted. The owners were still watching their shows. The devices were also routing traffic for ad fraud and giving criminals a hidden doorway onto home networks.

The January 2026 record attack worked the same way, except with home routers and security cameras instead of streaming boxes. 2 million devices, one coordinated attack, 31 terabytes per second. That's enough traffic to overwhelm most company networks in seconds, and it came from ordinary homes.

Why This Matters More for Higher-Value Homes in Serrano and Blackstone

More connected devices mean a larger attack surface. A starter home might have a router and a smart TV. A custom home in Serrano or Blackstone is more likely to have a full security camera system, smart locks on every entry, a video doorbell, an irrigation controller, whole-home audio, and a network-attached storage drive holding family photos and documents. Every one of those is a device that can run outdated firmware. Every one is a potential entry point.

Cameras and microphones add a different kind of risk. A hijacked camera doesn't just add to a botnet's traffic. It can also be used to watch a home's routines: when the house is empty, who comes and goes, what's visible through the windows. For families who already attract more attention because of the size of their home or their visibility in the community, that's a real exposure.

The same home network that runs the cameras and locks is usually the same network handling banking, brokerage logins, and email. A compromised device doesn't need to steal anything directly. It just needs to sit quietly on the network long enough to see what else is there.

What Happens to Your Smart Home Devices When You Sell?

Selling a home usually means transferring keys, garage remotes, and utility accounts. It rarely means resetting the security camera system, the smart lock app, or the Wi-Fi router, even though all three stay behind and keep working exactly as they did before the sale.

For the seller, that means a camera feed, a lock's access history, or a router's saved passwords can stay linked to an account they no longer think about. For the buyer, it means inheriting a network of devices with an unknown history: unknown firmware versions, unknown previous users, and no way to know whether anyone ever changed the default password in the first place.

We've started walking El Dorado Hills clients through this as a standard part of the moving conversation, the same way we'd talk through utility transfers or mail forwarding. It takes about twenty minutes, and it closes a gap that almost nobody else brings up.

Five Steps to Secure Your Connected Home Before You List or Move In

Securing these devices takes one pass through the home, the same way you'd walk through before a showing. Here's what to check.

1. Factory-reset every smart device before you sell, and again after you buy. Cameras, locks, thermostats, hubs, and routers all keep saved logins and Wi-Fi passwords until they're reset. A factory reset clears that and disconnects the device from the previous owner's accounts.
2. Replace default usernames and passwords. "Admin/admin" or "admin/password" is still the most common login found on hijacked devices. A unique password per device closes most of the door on its own.
3. Update the firmware, then turn on automatic updates. Manufacturers patch the vulnerabilities that botnets exploit, but only for devices that actually install the patch.
4. Put cameras, locks, and hubs on their own network. Most routers sold in the past five years support a second network, often labeled a guest network, built for exactly this. Keep it separate from the computers and phones used for banking.
5. Review linked accounts during a move. Camera apps, smart lock apps, and irrigation controllers are usually tied to a personal email and phone number. Moving is the moment to disconnect them.

Frequently Asked Questions About Smart Home Security for El Dorado Hills Homeowners

Do I need to reset smart home devices before I sell my house?

Yes. Cameras, smart locks, routers, and hubs should be factory-reset before closing, the same way you'd change door locks or remove a garage door code for an unfamiliar buyer. A factory reset disconnects the device from your accounts and clears saved Wi-Fi passwords, so the new owner starts with a clean device instead of one still linked to your phone.

What's the most common smart home security mistake El Dorado Hills homeowners make?

Leaving devices on factory-default usernames and passwords. It's the single most common way home devices end up part of a botnet, and it's also the easiest to fix. Every smart device, from a $40 camera to a whole-home automation hub, should have its own unique password.

Are smart locks and security cameras safe to use in a high-end home?

Yes, with basic upkeep. Smart locks and cameras from established manufacturers receive regular security updates. The risk isn't the device category, it's devices running years-old firmware or still set to default credentials. A home with five well-maintained smart devices is safer than a home with one neglected one.

How do I know if one of my home devices is part of a botnet?

Most homeowners never notice, which is part of the problem. Warning signs include a router or camera that runs unusually hot, a noticeable slowdown in home internet speed, or unfamiliar devices showing up in your router's connected-devices list. If you're not sure how to check, a factory reset and fresh setup with a new password resolves most cases regardless of the cause.

Should sellers disclose smart home technology to buyers?

Sellers should give buyers a list of installed smart devices and confirm that each one has been factory-reset and removed from the seller's accounts before closing. California doesn't require this as a formal disclosure, but it's part of a clean handoff, and it's the kind of detail that builds trust during a transaction.

The Bottom Line

Smart home technology adds real value to a home in El Dorado Hills, especially in Serrano and Blackstone, where buyers expect it. The 2026 botnet takedowns are a reason to treat that technology the way you'd treat any other part of the home during a transition: checked, reset, and handed over clean.

Jon Yoffie and Shannon Yoffie of Yoffie Real Estate Group walk El Dorado Hills buyers and sellers through this as part of every transaction involving a smart-equipped home, because it's a step that's easy to skip and expensive to ignore.

Sources: U.S. Department of Justice, March 2026 announcement on the disruption of the KimWolf, Aisuru, JackSkid, and Mossad IoT botnets; HUMAN Security Satori Threat Intelligence reporting on BADBOX 2.0; industry reporting on the January 2026 record 31 Tbps DDoS attack.

About the author: Jon Yoffie is co-founder of Yoffie Real Estate Group at 4359 Town Center Blvd, Ste 217, El Dorado Hills, CA 95762. He and Shannon Yoffie advise buyers and sellers across El Dorado Hills, Serrano, Blackstone, Folsom, and Cameron Park. Reach Jon at (916) 941-6566 or jon@yoffierealestate.com.