Helping people with computers... one answer at a time.

For a virus to infect a smart phone, it would have to be written specifically for that smart phone and poses little danger to your network system. But what kind of protection do you need for (and from) her laptop?

Leo, we recently installed a router so our computers could all share our internet access WiFi. Our granddaughter had been accessing the internet via her laptop and her smartphone. Now, for the big question: can a virus, etc., be transmitted to our system from either her laptop or her smartphone? She does not have a firewall on her laptop and her mom isn't sure if or which antivirus she has on the laptop and probably none on the smartphone. Second question: can a virus or other malware infect the Belkin router itself thereby spreading itself to all computers on the network? Any info would be appreciated.

In this excerpt from Answercast #10, I talk about the steps to take to protect your network from the unknown dangers coming from your granddaughter's laptop... while she learns about internet safety.

Smartphone viruses & malware

So first of all, from your computer's point of view, I would not be concerned about the smartphone. Malware that infects a smartphone is (first of all, there isn't very much of it) and by definition, it almost has to be tailored to that smartphone; that model of smartphone or that operating system.

It's not that big of a target for malware authors these days and you just don't see a whole lot of it. It's coming, but it's not there today.

The bottom line, though, is even if it is infected, that's not the kind of malware that could infect your Windows-based PC. You would need Windows-based malware to do that.

Laptop security

Now that opens up the other question: what about her laptop?

She's not using security on her laptop which is actually, honestly, fairly troubling. If you don't know if she's running antivirus at all, that's kind of scary.

Whether or not she has a firewall -- I'm not as concerned about that as long you guys are all behind a router, because that router provides a first level of firewall protection. That is so important when connecting to the internet.

More importantly, if you've got a child's computer on the internet, and you can't trust the child, then you can't trust the person's who's running that system to understand how to be secure.

Secure your system

It's not her computer that needs the firewall - it's yours.

You need to protect yourself from her computer.

You need to act almost as if you were out on the naked internet. That means making sure that you have a firewall of some sort between your computer and hers. You should enable a software firewall, the Windows firewall on your machine, and on every other machine that's on that network.

I do have an article on protecting yourself from your children where this is basically the topic at hand.

It's important that kids learn about internet safety, but it's also unrealistic to think that they will always use the right techniques and always stay as safe as we would want them to be.

Virus on the router

So, can a virus or other malware infect the router itself?

I have never heard of a virus, a Windows virus, that actually infected a router or was transmitted by a router.

So in that sense, I think that your machines are safe from getting malware from the router.

There is a scenario, however, where the router is involved. It is possible to get malware on your machine that then reconfigures the router. The router isn't really infected. It doesn't have malware on it, but the malware that's on some other machine gets administrative access to the router and resets many of the configuration parameters.

The most important configuration is where your systems go to look for DNS.

DNS is that thing that maps the names, say, to a specific IP address or to specific server on the internet. If malware inserts a bad DNS server in there, they can route you to their own servers: their malicious servers.

If they are mimicking Paypal, you could think you are interacting with Paypal. There might be no indication that you're not interacting with Paypal, and yet because of the router having steered you wrong, you're interacting with a completely malicious site.

What's important there (and I have an article on that) is: How to do I secure my router? There are several steps you will want to take to make sure that the router itself is secure and protected from these kinds of malicious attacks.

Back to - Answercast #10

Article C5226 - April 19, 2012 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

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