Reboot Remedy for Better Security

A common tech support trope is asking the customer “did you trying turning it off and back on again?” Quite often that will reset an misbehaving system. But it can also completely purge malware. Let me explain.

The Power of Rebooting

Electronic devices often have some sort of state information. What mode am I in? What temperature am I set at? What am I doing right now and what should I do next? This requires some sort of memory. If a device gets stuck in an electronic ditch, the simplest solution is just to turn it off and back on again. This will reset most devices to a startup state, making them functional again.

Just about any device today that you can plug in contains some form of computer chip. Computers run software. And software can get corrupted – either intentionally via malware or just via a bug in the code. The manufacturer’s software comes preinstalled and is more or less permanent. But malware is (usually) preinstalled and it’s often not persistent. Malware infecting a device may only reside in the device’s volatile memory (RAM), as opposed to its non-volatile memory (hard disk). When you reboot the device, the volatile memory is wiped clean – and therefore, any malware that was only resident in RAM will be purged.

In addition to removing malware residing only in RAM, rebooting many of these device that run for long periods of time can often improve their performance. Over time, certain resources can get tied up – restarting the device can clear out the cruft.

What Devices to Power Cycle

So what type of devices would most benefit from this procedure? Honestly, any device could benefit. However, the following devices would be more likely to be fixed by rebooting if they were infected with malware.

1. Home Routers and Modems: These devices are often vulnerable to malware that resides in memory. Furthermore, these devices are directly exposed to the internet, which make them prime targets.
2. Smartphones and Tablets: Given how frequently these devices connect to the internet, they can pick up temporary malware. Modern iOS and Android devices have pretty good security, but it’s easy to reboot them, so why not?
3. Smart TVs and Streaming Devices: Your smart TV and streaming devices run complex operating systems that can run apps, and they constantly interact with the internet.
4. IoT Devices (like webcams, smart appliances, and thermostats): Often overlooked, these devices can also be compromised by malware. And as we like to say, the “S” in IoT is for security.
5. Printers and Network Devices: Modern network printers and devices like switches can harbor malware in their memory.
6. Gaming Consoles (like Xbox, PlayStation, or Nintendo Switch): These consoles are really just specialized computers, with internet access and downloadable apps.
7. Computers (desktops and laptops): Malware on computers can often persist on the hard drive, but some computer malware might be only in memory.

How to Purge Malware Via Reboot

For many devices, all you need to do to purge everything from memory is just restart or reboot it. If the device has an on/off switch, you can turn it off for 30-60 seconds and turn it back on.

However, to properly reset the memory of devices that plug into the wall, even ones with a power switch, you may need to actually unplug them to clear the RAM. For example, smart TVs, game consoles, and some IoT devices may only go into a standby or sleep mode when turned “off”. Check the manual to be sure. Look for instructions on how to do a “soft reset” of the device. (A “hard reset” will return the device to factory settings, which means you’ll have to reconfigure it completely.)

Finally, you should also be updating your devices’ software (sometimes called firmware), where you can. When you update the software, this will require the device to reboot.

Final Thoughts

Restarting a device may remove any malware running in memory, but it’s not a silver bullet. If that device was infected once, it could be infected again – unless you’ve updated the software on the device and fixed the vulnerability that was exploited. For this and other reasons, you should ideally restart your devices periodically. If you can, I would reboot your router, modem, smartphone and tablets once a month at least. The other devices can probably be done less often. So set yourself a reminder and power cycle your key devices periodically.

Note that often times malware on IoT devices doesn’t interfere with their normal functioning. You might not notice anything unusual. Instead, the bad guys can use your compromised devices to attack other computers, masking the identity of the attacker. When attackers recruit multiple compromised devices, they create what’s called a botnet. Collections of thousands or even millions of commandeered IoT devices have been used to do a lot of damage. So periodically rebooting your devices is not just good digital hygiene – it’s also good for the general internet welfare.