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.
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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.
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
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 is that thing that maps the names, say Paypal.com, 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
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
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