Default passwords on network devices

What’s the threat?

The notorious Mirai malware is one of the most dangerous botnets around and is designed to infect Internet of Things (IOT) devices, ranging from wireless routers to network cameras. It recently even made the jump to Windows PCS.

Once a device is infected, cybercriminals can control it remotely, forcing it to take part in internet attacks on websites. More worryingly, an infected device is also a weak point in your home network, potentially allowing a hacker to steal private data.

What should you do?

First, you should check if any of your internet devices are vulnerable to hackers. Bullguard’s IOT scanner ( iotscanner.bullguard.com) is a good starting point. On the website click the big ‘Check if I am on Shodan’ button (Shodan is a search engine that finds IOT devices that are publicly accessible on the internet). If no devices are found, you can click the ‘Deep Scan’ button to perform a more thorough check.

If the scan detects problems, it means you’re at risk. Even if it doesn’t, you should still make changes to avoid future threats. Go to the setting panel for each network-connected device (the device’s manual will tell you how). Mirai uses a database of common usernames and passwords to infect devices, so changing the default password is your first priority. Mirai can also infect devices with security flaws, so follow the user guide to perform a software update on each device.

Finally, you should disable the UPNP feature on your router (again, refer to the user manual – see screenshot). This setting lets devices automatically configure your router but can be misused to allow hackers into your network. Disabling the feature can stop some devices working properly, requiring manual configuration. It’s a trade-off between effort and security.