Quick Take

• IoT botnets are emerging as a significant cybersecurity threat.
• Attackers take advantage of insecure devices, many of which are lingering around home and corporate networks.
• Hijacked IoT devices are fueling large-scale attacks, such as DDoS and ransomware campaigns.
• Organizations require improved security policies, including better firewall settings and network segmentation.

Introduction

I’ve been in this field for decades—before we manually configured routers to even get a connection, back when phones lived on PSTN networks. And I’ve witnessed some really nasty crises hit the internet (Slammer worm, anyone?) … but this IoT botnet mess we have this moment? It’s a different beast.

Here’s the thing. To this day most companies still fail to take IoT security as seriously as they should. I recently helped three banks with zero-trust architecture upgrades, and wouldn’t you know it? All three had completely dismissed IoT devices in their original security reviews. Cameras, smart TVs, badge readers — just sitting there, waiting to be hijacked.

IoT appliances spread like a virus these days, from smart doorbells to industrial control systems, and improper security can make them ridiculously easy to exploit if they aren’t secured. Hackers know this, and they’re weaponizing them at an absurd scale.

How IoT Botnets Work

In concept, Internet of Things (IoT) botnets are straightforward — take control of thousands (or millions) of unsecured devices and use them to stage attacks. But the way attackers do this in the wild? That’s where it gets ugly.

Here’s what a typical IoT botnet attack looks like:

1. Scanning for Targets:

   Attackers scan the internet for IoT devices using automated tools. This is just plain stupid easy when: Default passwords, no patched firmware, open ports.

2. Infection and Control:

   Malware like Mirai (or one of its 100+ variants) hit devices. After infection, they call home to the attacker’s control server.

3. Launching Attacks:

   These botnets can be used for DDoS, credential stuffing, ransomware delivery, and even proxying cybercriminal activity. Because they’re real devices injecting into normal networks, they work around traditional security mechanisms.

And here’s the worst part? Most owners are unaware their device has been compromised.

Real-World Attacks

I remember Mirai being in the news for the first time—this was in 2016. Watching a botnet-fueled assault take down sites such as Twitter and Reddit was at once exhilarating and terrifying.

But it didn’t stop there. Attackers have only become more adept at peddling IoT devices as weapons:

• Mirai: Still roaming free, spreading routers, security cameras, and DVRs with default passwords.
• Mozi Botnet: Smartly utilizes peer-to-peer networking—so takedown is much harder.
• Torii Botnet: More stealthy, designed to survive reboots and updates.

And more recently? One of the talks I endured at DefCon was about botnets attacking industrial IoT (IIoT). That’s right — we’re talking power grids, factories, and water supplies. If that doesn’t keep CISOs up at night, I don’t know what will.

Prevention Strategies

Alright, let’s get practical. How to stop IoT botnet infections before they spread into your network.

For Businesses & Enterprises:

• Use appropriate firewall rules to reject unneeded egress—don’t allow IoT devices to communicate with arbitrary external servers.
• Employ deep packet inspection (DPI) to identify anomalies.
• Implement network segmentation. For example, don’t put your security cameras on the same VLAN as your corporate data. Keep your IoT devices on a separate network to limit the impact if something becomes infected.
• Turn off default credentials immediately. If a device doesn’t let you change the default password, replace it.
• Ensure regular patching & remediation. Schedule manual patching for devices that lack automatic updates.
• Employ endpoint detection & response (EDR) solutions to monitor for abnormal device behaviors.

For Consumers:

• Change default passwords right away.
• Disable unused ports & services on IoT devices.
• Create a dedicated IoT Wi-Fi network to separate your smart devices from more critical devices.
• Monitor router logs for unusual activity or penetration attempts.

Look, I get it. Security updates are a pain, and no one likes to mess with technical settings on their home router. But what if your smart thermostat—or your surveillance cameras, worse—is part of a botnet attack? That’s on you.

Future Trends (And Why We’re Not Out of the Woods Yet)

IoT security’s future doesn’t exactly look great. AI-powered botnets? Already a thing. Hackers are applying machine learning to automate exploitation, evade security measures, and adapt defenses.

Here’s what’s coming:

• More Intelligent Botnets: Self-healing, decentralized, and harder to disrupt.
• Additional IIoT Attacks: Targeting industrial sectors like smart cities, wired healthcare, and autonomous vehicles.
• AI-Based Protections: While marketed aggressively, AI may not catch up to advanced exploitation at scale.

And how about the 75+ billion IoT devices estimated by 2025? We’re sitting on a time bomb.

Final Thoughts

IoT botnets are not solely an IT problem—they’re a business problem. A national security problem. A giant headache for anyone who works in cybersecurity.

If you’re in charge of a company, an enterprise, or even IT at your home, here’s what you need to do:

• Do an inventory of every IoT device on your network.
• Implement strong security policies.
• Enforce network segmentation and firewall rules.
• Stay updated with patches and emerging threats.

Look, attackers thrive on negligence. Don’t be an easy target. And if you’re ever unsure about whether your network is already compromised, reach out to a cybersecurity expert—preferably before your devices become part of an attack on someone else’s network.