Security and wireless internet

Some families in my neighbourhood are using wireless internet without any
security.

I know that using security (password or Mac-address filtering) is often
advisable, but I would like to know better what risks are involved by having
an open wireless network:

1) Can virus spread across a wireless network between computers which are
only sharing the internet connection?

2) Is it possible for users sharing an internet connection to gain access to
files on other computers sharing the connection?


Thank you

Erik

Erik wrote:
> Some families in my neighbourhood are using wireless internet without any
> security.
>
> I know that using security (password or Mac-address filtering) is often
> advisable, but I would like to know better what risks are involved by having
> an open wireless network:
>
> 1) Can virus spread across a wireless network between computers which are
> only sharing the internet connection?

Yes, if the network is configured in a suitable way.

> 2) Is it possible for users sharing an internet connection to gain access to
> files on other computers sharing the connection?

Yes, if the network is configured in a suitable way.

But the main reason for protecting the network is to avoid inappropriate
use of the internet connection. Not just overloading it, but sending
spam, or attacking remote computers. There have been several cases in
several countries where the owner of an open WLAN was accused for a
crime that was perpetrated by an anonymous visitor.

An open WLAN is like an open wound in the belly of the Internet.

-- Lassi

"Erik" <erikbach-fjerndette-@stofanet.dk> writes:

> Some families in my neighbourhood are using wireless internet without any
> security.
>
> I know that using security (password or Mac-address filtering) is often
> advisable, but I would like to know better what risks are involved by having
> an open wireless network:
>
> 1) Can virus spread across a wireless network between computers which are
> only sharing the internet connection?
>
> 2) Is it possible for users sharing an internet connection to gain access to
> files on other computers sharing the connection?

answered in the other group you also posted this too.

For future reference, cross posting vs separate or multi-posting helps
keep the question and and replies less fragmented.

--
Todd H.
http://www.toddh.net/

"Erik" <erikbach-fjerndette-@stofanet.dk> writes:

>Some families in my neighbourhood are using wireless internet without any
>security.

>I know that using security (password or Mac-address filtering) is often
>advisable, but I would like to know better what risks are involved by having
>an open wireless network:

>1) Can virus spread across a wireless network between computers which are
>only sharing the internet connection?

Perhaps.

>2) Is it possible for users sharing an internet connection to gain access to
>files on other computers sharing the connection?

Perhaps.

If someone gets onto the internal net, there are almost never any firewalls
between the computers and that wireless. Ie, you lose all of the defence
that any firewall has.
Aalso since it is on the internal network, the computers may be set up for
file sharing ( network neighbourhood) between any two computers on the net.
Clearly that also is a disaster.

If each computer is set up under the assumption it is completely accessible
and defences on that computer itself have been set up under that assumption
then the possiblility of security comprimise is lessened.

However the rogue user can mimic that internal network, get free downloads
(eg if you have limits on the amount of material you can download/upload)
spam others as if it came from you (it does) etc.



>Thank you

>Erik

Erik <erikbach-fjerndette-@stofanet.dk> wrote:
> 1) Can virus spread across a wireless network between computers which are
> only sharing the internet connection?
> 2) Is it possible for users sharing an internet connection to gain access to
> files on other computers sharing the connection?

If there are file services enabled on this computers: yes.

Yours,
VB.
--
"Life was simple before World War II. After that, we had systems."
Grace Hopper

Open access to wireless routers is a major issue for all parties
involved. One, if any networking is configured, and you are on the
internal network, a breach is not very difficult. Two, if the person
that accesses the router (let's say yours) is a "power user", they will
be able to sniff your traffic for credit card numbers, etc, since most
home routers broadcast the majority of traffic to anyone. Even if the
router doesent, they can make it do so. They can also download
anything, movies, music, child porn, whatever. The router owner is
often times stuck with this, unless they log the router (which is a
growing trend). The above things are all things that most wireless
routers know. Now let's look at the euphoric world of the bandwidth
stealer. You generally only hear good things for them, free internet
with 0 liability. Using someone else's router gives them the same
abilities to hack you as you do to hack them, aside from them not being
liable for the internet traffic. Back hacking is a game I'm hearing
more and more of where hackers open a router but throttle it so they
can find easy computer targets. Another more malicious attack is
available though. If someone sets up a computer to pass data through,
they can log all of your information. Let's say turning a linux box
into a wireless router. The machine can be configured with pre-built
webpages like banks, ebay, amazon, etc. This is easy to do since you
really only have to do the login page, take their user/id and password
and pass it to the bank, or just put up a "this page is temporarily
unavailable screen". Other instances are faking being a commerical
hotspot, where many make you download a bit of software to use them.
This software can turn out to be a backdoor into your computer, a
virus, whatever. WEP does not fully protect against this either, since
you can break WEP. I would recommend not using wireless networks if you
dont want to risk anything.

On Dec 9 2006, 5:21 pm, Volker Birk <bum...@dingens.org> wrote:
> Erik <erikbach-fjerndet...@stofanet.dk> wrote:
> > 1) Can virus spread across a wireless network between computers which are
> > only sharing the internet connection?
> > 2) Is it possible for users sharing an internet connection to gain access to
> > files on other computers sharing the connection?If there are file services enabled on this computers: yes.
>
> Yours,
> VB.
> --
> "Life was simple before World War II. After that, we had systems."
> Grace Hopper

requeth@gmail.com wrote:
> I would recommend not using wireless networks if you
> dont want to risk anything.

Maybe endpoint to endpoint encryption will help for the risky parts.

Yours,
VB.
--
"Pornography is an abstract phenomenon. It cannot exist without a medium
to propagate it, and it has very little (if anything at all) to do with sex."
Tina Lorenz
<https://events.congress.ccc.de/congress/2006/Fahrplan/events/1422.en.html>