How can smart home systems be made secure?

13 Tem 11:38

Last month, I installed a new smart heating system in my home, and a few days after installation, I started getting strange notifications from the manufacturer's app. First, I changed the network settings, strengthened the default password, and separated my Wi-Fi network with a VLAN. Then, I blocked unauthorized access to the system and set it to automatically install device updates. I only access the central unit via VPN and use two-factor authentication.

13 Tem 13:43

Wow, dude, smart home systems have really become a topic that keeps you up at night these days. When it comes to IoT device security, it's not enough to just say "set a strong password." On the device side, what do we have? Weak default passwords left in factory settings, unupdated firmware, and even some manufacturers' backdoors. If the device isn't running a fully privileged Linux/Yocto/Buildroot and the manufacturer has stopped supporting it, you should immediately remove it from your network. To meet the minimum security standard for devices, certified products should be preferred (e.g., Zigbee Alliance’s Certified or Matter standard), but even a certificate isn't always enough. Manufacturer-specific exploits can emerge at any time, so don't rely solely on certification. Now, let's talk about the network side. First, IoT devices must be placed in a dedicated VLAN. If all devices are on the home's main network and one gets hacked, it can spread to others, putting all your data at risk. VLAN separation not only controls access but also limits the spread of attacks. Using a DNS sinkhole to block known malicious domains (botnet C&C servers, cryptojacking hosts, etc.) is also very useful. For Wi-Fi systems with mesh networks, fine-tuning like disabling Broadcast SSID, using WPA3, and making the PSK complex comes into play. But the most important thing is to restrict IoT devices' internet access as much as possible. For example, allow the device to access only the ports and IPs it needs and block the rest with a firewall. You mentioned a central control unit—yes, it's also an IoT device, and it can compromise your entire system if breached. So, the central system should ideally stay offline except for local access, or be accessible only via VPN. Additionally, you should log and immediately block anyone trying to access the system without multi-factor authentication (MFA). Furthermore, the services running on the central system must follow the principle of least privilege; otherwise, an exploit could lead to a data dump. Finally, setting up a system that automatically updates these settings and having an emergency response plan for any alerts is a must.