Smart Home Security Risks
Passwords, a Separate Device Network, Guest WiFi and Updates

What the real risks are

Smart home security is rarely about a skilled attacker targeting your house. It is about the same small mistakes repeated across millions of homes, which automated tools find cheaply. A camera still using the password printed in its manual, a plug whose maker stopped releasing fixes, a router with remote admin left on: each of these is an open window that nobody needs to break.

The UK’s National Cyber Security Centre puts it plainly in its guidance for households: a device is not secure if a criminal can guess the password used to access it, because that lets them log in and use it to reach the rest of your network. The same guidance notes that makers release updates to fix security issues, and that a device without those fixes becomes easier to hack. That advice is written for the UK, but the devices and the habits are the same here.

Start with the router

The router is the front door of the home network, and it has two passwords that people mix up. The WiFi password lets devices join the network. The admin password lets someone change the router’s settings. Provider routers often arrive with an admin login printed on a sticker or shared across many units, so change it first and keep it somewhere safe.

• Change the router admin password and switch off remote administration unless you truly use it.
• Use WPA3 if your router and devices support it; the Wi-Fi Alliance says WPA3-Personal gives increased protection from password-guessing attempts. Many older smart plugs accept only WPA2, which is still fine with a long password, and a mixed WPA2/WPA3 mode can serve both.
• Switch off the push-button and PIN pairing feature (WPS) if you never use it.
• Check the router app for firmware updates, and turn on automatic updates where offered.
• If the provider has locked a setting, ask the provider rather than replacing the router blindly.

Changing the WiFi name or password will knock every smart device offline until each one is re-paired, so plan it for a quiet evening. The guide to devices going offline after a WiFi change explains how to bring them back without resetting everything.

A separate network for smart devices

Putting smart devices on their own network is the single most useful step after passwords. If a cheap plug or camera is ever compromised, it can only see the other gadgets, not the laptop with your banking or the phone with your photos. Many routers offer a guest network that does exactly this; better routers and mesh systems let you create a dedicated network for smart devices with its own name.

There are trade-offs. Some apps find devices only when the phone is on the same network, so first-time set-up may need the phone to join the device network for a few minutes. Casting to a TV, local control and some voice assistants also expect everything to sit together. Test the routines you use daily after the split, and keep the smart home hub where both the phone and the devices can reach it. Zigbee and Thread devices talk only to their hub, so isolating the hub isolates them too.

Guest WiFi for visitors, tenants and helpers

Visitors should never get the main WiFi password, because once given it is impossible to take back without changing it for every device. A guest network with its own password solves that. For a home that is rented out by the night or the month, the guest network becomes the only one guests see, and its password changes between stays; the guide to smart locks for Airbnb and rentals covers door codes on the same principle.

A live-in helper or a regular cleaner may need a few devices, such as the door lock or the aircon controls, without access to the cameras or the router. Give them their own app login with limited permissions rather than the owner’s account; the guide to smart home access for a domestic helper goes through what to share.

App accounts: the part people forget

Most smart devices are really controlled by an account in the maker’s cloud, not by the device itself. Whoever owns that account owns the house’s controls. Make sure every app account, from the lock to the cameras to the hub, is registered to the household’s own email, with a password that is not reused anywhere else.

• Turn on two-step verification wherever the app offers it, as the NCSC recommends.
• Share access with family through the app’s home member or sharing feature, never by sharing a password.
• Review the list of members and connected services every few months and remove anyone who should not be there.
• Remove the installer’s access once the job is handed over.
• Keep a written list of which app controls which device, stored somewhere safe.

When you move house or sell a device, the accounts matter as much as the hardware; the guide to resetting a smart home when moving covers the handover in order.

Updates and support dates

Turn on automatic updates in every app that offers them, and install manual ones when prompted. Updates are how makers close the holes that attackers already know about. The less obvious step comes before buying: the NCSC advises avoiding devices whose maker no longer supports them, or whose support will end soon, and suggests treating the support end date like a use-by date.

In practice this means preferring brands with a real local presence and a track record of app updates, and being cautious with unbranded gadgets sold only on marketplaces. A device that still works but no longer receives updates is best retired, or at least kept on the smart device network where it cannot reach anything important.

Cameras and microphones

Cameras deserve the most care because their footage is the most personal data in the house. Point indoor cameras at entrances and corridors, not at bedrooms or bathrooms, use the privacy mode or a schedule when the family is home, and choose local storage on a card or recorder if you do not want footage in the cloud. If you never view a camera away from home, the NCSC suggests switching off remote access altogether.

Smart speakers and displays listen for their wake word, and most have a physical mute button. Use it in rooms where private conversations happen. For linking existing CCTV into a smart home app without opening it to the internet, see the guide to linking CCTV to a smart home app; the trade-offs between WiFi cameras and a wired system are in the WiFi camera vs professional CCTV guide.

Cameras, tenants and helpers: personal data

A camera that records a helper, a tenant, short-stay guests or the shared corridor raises personal data questions under Malaysia’s Personal Data Protection Act 2010, especially where the home is used for a business such as a homestay. This page does not give legal advice. If you rent out the home or employ staff, read up on the Act or ask a lawyer before relying on footage, tell the people who are recorded where the cameras are, and keep recordings no longer than you need them. In a condo, check with the management office before pointing anything at common areas.

Before you buy a device

• Check the MCMC label on the box or device, and look up its details on MCMC’s Check Your Label service rather than trusting the look of the sticker.
• Prefer devices that can keep working locally if the internet or the maker’s cloud goes down.
• Check whether the app lets you share access, set up two-step verification and see the device’s update status.
• Avoid buying the same brand in different regional versions, which can lock you into separate apps and servers.

Local control is a security benefit as well as a reliability one, because fewer commands travel through a distant server; the guide to a smart home that works without internet explains which devices can do it.

Warning signs and what to do

If you believe someone has taken control of a device, the NCSC’s advice is to reset it using the manufacturer’s instructions. Before selling or giving a device away, do a factory reset so your data and account links go with it.

How we help

We set up the router, the separate smart device network and the guest network, move each device onto the right one and test the routines afterwards. We do the smart device, app and low-voltage side of the job. We register every app account in the owner’s name, help turn on two-step verification and automatic updates, and hand over a list of devices and apps. Alerts from cameras and sensors go to your own phone, and you decide who in the family receives them.

Sources & references

• UK National Cyber Security Centre, Smart devices: using them safely in your home: passwords, two-step verification, remote access, updates, support dates and resets (UK guidance).
• Wi-Fi Alliance, Wi-Fi security: WPA3-Personal and protection from password guessing.
• MCMC Check Your Label (cyl.mcmc.gov.my): looking up a device’s certification label.
• ClickBina guides on devices offline after a WiFi change, Airbnb locks, helper access, resets when moving, CCTV linking and local control, linked above.