Are there any further security considerations when joining a public wifi network other than firewall and anti-virus?

Question

If I use my laptop on my company wifi network to use the internet, what access has the company to the laptop hard drive and information on it? The company wifi is there for customers and employees (in their personal time) to access the internet so is acceptable to use it for this purpose.

Although a company domain exists, I won't be part of this as I'll only be logging on to the wifi access point in order to gain access to the internet

I use my company wifi as an example but this is also a relevant question with regard to public wifi access points too - for the purposes of this question I shall just refer to the company context even though it applies to both...

With my 'access' to the internet being through the VPN, I presume this is sufficient to prevent the wifi access point operator from snooping on my internet traffic but my main concern is whether they could gain access to the hard drive through the connection to the wifi access point itself.
I guess this question would also be applicable to a wired connection too???

Whilst there is nothing nefarious I wish to hide, I do not want any of my hard drive data being exfiltrated by snoopers as this is personal data. Would the operator of such a wifi access point have any access to hidden or administrative shares

I use a reputable firewall / anti-virus software as well as a VPN on my laptop and keep the OS up to date with patches etc.

Is there any way to test the vulnerabilities without needing to employ a pentester!! Is there any software which can be used to scan for such vulnerabilities?

The obvious thing is not to use the laptop on a company of public wifi of course...I use a reputable firewall and anti-virus software on my laptop and keep the OS up to date with patches etc.

Answer 1

Connecting to a Wi-Fi network means that any other devices on network may be able to see the activity between you and the router.

If you connect to a VPN right after joining the Wi-Fi network, they won't be able to see that traffic anymore.

Nobody on the network, including the owner of the router, will be able to reach into your computer and look at the hard drive just because you're on the same network. They will be able to see open ports on your device, if:

• You're not on the VPN yet
• You're not using any kind of firewall

As long as you take care of those two points, your computer will not be able to be snooped on by others on the Wi-Fi and they won't be able to make connections to network services on your computer.

Note that some things can still go wrong. Your firewall rules may be too permissive and a port may be exposed. Or you might forget to turn on the VPN. In this case, an attacker might be able to run an exploit and gain access to your computer.

If you want to test this yourself, you could use a second computer and run a tool like nmap, nessus, or openvas to run a scan of the open ports and services running on your computer. These tools can give you an idea of what an attacker on the network might see.

Answer 2

In addition to the previous answer, when you turn on VPN, existing connections may continue without VPN. So if you turned on VPN after starting your browser or running connected apps, turn the breaker/apps off and restart them. And only use https, which you should do anyway.

Your Wi-Fi itself is encrypted, but someone on the same network as you can break that encryption much easier. On your home network only you and friends and family should be on the network, nobody else. On a public network, it could be anyone.