WiFi security from another authorized user (roommate)

Question

I believe we use WPA or WPA2 encryption.

To what extent can another user monitor my traffic?

• Monitor my desktop activity?

• View documents I've saved on my computer?

• Tell what sites i visit?

• Tell what my passwords / logins / email addresses are?

Is there any way I can tell if I'm being monitored? If so, how can I stop it?

Answer 1

You can be monitored when you are on the same wifi network and the other person uses a wifi antenna that is in promiscuous mode. He can only see what traffic you are sending over the wifi network. If you are sending your journal over the internet without using HTTPS, he will be able to see them.

Your internet can be actively monitored, at least where you are going. There are countermeasures like using an encrypted VPN or SOCKS proxy.

Again for your passwords, if you are visiting the site in HTTP rather than in HTTPS, than anyone that has access to a point between you and the webserver will be able to see your credentials.

Solutions:

• get your own wifi
• invest in an encrypted vpn
• invest in a SOCKS proxy server
• Use HTTPS

P.S. This is the same for Mac and PC.

Answer 2

Your question is very broad. Keep in mind that not everything on your computer is transmitted via wifi.

Monitor my desktop activity?

View documents I've saved on my computer?

Tell what sites i visit?

These aren't exactly functions of having wireless internet. I mean if you save a document to your local hard drive it would never be on the internet (or any network for that matter) so wifi is out of the picture.

Tell what my passwords / logins / email addresses are?

This has more to do with wifi. You want to make sure the channel you use to connect to your wireless access point (e.g. router) is secure so that others in the area can't snoop what's being transmitted.

To find out if your being monitored could be lengthy proccess since there's so may ways to monitor someone. Do you have guesses where to start looking? e.g. on your computer itself or on the router.

Answer 3

There are 3 possible answers to your question.

A) If your WiFi is indeed protected by WPA2 and no one has the password than you are perfectly safe with the assumption that you trust whom ever is on your network...now with that said there is one exception. That if someone skilled enough wants to enter your system then they will and its only a matter of time. However these people are rare...very rare!

B) Second, if your being protected by WPA...then the likelihood of your system being compromised increases with the same above information applying. However with one change, a bit less skill is required and some free tools with a skilled person behind them can compromise your network. Why do you think they crated WPA2...

C) If anyone is on your network at all with the password or they have a wired connection to your router/switch/hub you are completely vulnerable and have little to 0 defenses short of having a PC side VPN. Not to confuse this with a edge device VPN as that encryption does not take effect until the data hits the edge and is clear text as it passes through LAN.

Basically, once someone is IN your network and you don't have a VPN setup on YOUR MACHINE...they can see everything you transmit.

Now the question is un-answerable once we discuss Linux/MAC OS X/ Windows discussions of permissions and exploits ect...so no I wont spend 8 hours discussing exploits for those 3 platforms.