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WPA/PSK

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Anonymous
a b F Wireless
November 10, 2004 2:55:21 AM

Archived from groups: alt.internet.wireless (More info?)

It says in WEP that you have to change the key.It says with WPA/PSK it
changes it for you. How? And do I have to change it?

Thanks in advance....
kevin

More about : wpa psk

November 10, 2004 4:04:14 AM

Archived from groups: alt.internet.wireless (More info?)

"Kevin" <kevstacey41@btinternet.com> wrote in news:cmrld8$b5s$1
@sparta.btinternet.com:

> It says with WPA/PSK it changes it for you.
OK.

> How?
Magic. Or some technical stuff.

> And do I have to change it?
No because "It says with WPA/PSK it changes it for you".
Anonymous
a b F Wireless
November 10, 2004 8:23:16 AM

Archived from groups: alt.internet.wireless (More info?)

Taking a moment's reflection, Kevin mused:
|
| It says in WEP that you have to change the key.It says with WPA/PSK it
| changes it for you. How? And do I have to change it?

The change that is referenced is the key to each packet. The key is a
function of the passphrase you select. The problem with WEP is that this is
a static key that never changes. So, if you collect enough meaningful
packets, you can eventually reconstruct (software "guess") what the key is.
However, WPA corrects this by negotiating the initial connection with the
original passphrase based key, but then changes the key automagically at the
specified interval (setting in router or AP). You should still change your
WPA-PSK passphrase periodically, however.
Related resources
November 10, 2004 1:29:32 PM

Archived from groups: alt.internet.wireless (More info?)

"mhicaoidh" <Rêmõvé_mhic_aoidh@hotÑîXmail©PäM.com> wrote in message
news:Bzhkd.320598$wV.198673@attbi_s54...
> You should still change your
> WPA-PSK passphrase periodically, however.

Why? and exactly how often?

Regards,

M
Anonymous
a b F Wireless
November 10, 2004 2:32:42 PM

Archived from groups: alt.internet.wireless (More info?)

On Wed, 10 Nov 2004 10:29:32 +0100, Misiek spoketh

>
>"mhicaoidh" <Rêmõvé_mhic_aoidh@hotÑîXmail©PäM.com> wrote in message
>news:Bzhkd.320598$wV.198673@attbi_s54...
>> You should still change your
>> WPA-PSK passphrase periodically, however.
>
>Why? and exactly how often?
>
>Regards,
>
>M
>

Because the passphrase is used for initial authentication, and if
someone can figure out your passphrase, then they can connect to your
WLAN... How often? Well, that depends on how secure you think your
passphrase is.

Lars M. Hansen
http://www.hansenonline.net
(replace 'badnews' with 'news' in e-mail address)
Anonymous
a b F Wireless
November 10, 2004 10:12:23 PM

Archived from groups: alt.internet.wireless (More info?)

Taking a moment's reflection, Misiek mused:
|
| Why? and exactly how often?

In addition to Lars' comments, while WPA is more secure than WEP,
WPA-PSK is still subject to so-called "dictionary" attacks. If someone has
the time and resources, they can simply try known and random combinations of
characters to try and crack your WPA-PSK passphrase. The more complicated
the passphrase, the longer it will take. Changing it every so often
decreases the likelihood of someone cracking it in this manner.
Anonymous
a b F Wireless
November 12, 2004 2:19:47 PM

Archived from groups: alt.internet.wireless (More info?)

On Wed, 10 Nov 2004 19:12:23 GMT, "mhicaoidh"
<®êmõvé_mhic_aoidh@hotÑîXmailŠPäM.com> wrote:

>In addition to Lars' comments, while WPA is more secure than WEP,
>WPA-PSK is still subject to so-called "dictionary" attacks. If someone has
>the time and resources, they can simply try known and random combinations of
>characters to try and crack your WPA-PSK passphrase. The more complicated
>the passphrase, the longer it will take. Changing it every so often
>decreases the likelihood of someone cracking it in this manner.

I'd be interested in knowing time periods on this.

Supposing someone uses 128bit WEP. They use their connection only in
the evenings (I make that point on the assumption that capturing
network traffic requires there to be plenty of traffic to capture) and
only for web browsing, writing documents etc. How long,
realistically, would it actually take someone to capture enough
information to allow them to determine the key (and how long would
determining the key itself take?).

Now, what about the same question as above but using WPA-PSK with a 56
character key including upper and lower case, letters, numbers and
some ascii characters such as underscores, dashes, asterisks etc (the
final result being an unintelligable jumble.

Weeks, days.... hours?

Add to that software firewalls on all LAN computers, access only to
files only by particular usernames yadda yadda yadda. My hacking
abilities are nil, so I find all of this stuff interesting.
Anonymous
a b F Wireless
November 12, 2004 2:19:48 PM

Archived from groups: alt.internet.wireless (More info?)

On Fri, 12 Nov 2004 11:19:47 +0000, Simon Pleasants spoketh

>
>I'd be interested in knowing time periods on this.
>
>Supposing someone uses 128bit WEP. They use their connection only in
>the evenings (I make that point on the assumption that capturing
>network traffic requires there to be plenty of traffic to capture) and
>only for web browsing, writing documents etc. How long,
>realistically, would it actually take someone to capture enough
>information to allow them to determine the key (and how long would
>determining the key itself take?).

Assuming there's enough activity, about 1 hour.

>
>Now, what about the same question as above but using WPA-PSK with a 56
>character key including upper and lower case, letters, numbers and
>some ascii characters such as underscores, dashes, asterisks etc (the
>final result being an unintelligable jumble.
>
>Weeks, days.... hours?
>

Since it would be essentially brute force cracking, that would mean that
they'd have to try every possible combination. Now, there's 26 letters
and 52 counting upper case, plus 10 numbers and let's say 18 special
characters just to make it easy on me ... With 56 characters, that would
be 60^56, which is 3.77e99 combinations. According to my sources, Lopht
takes about 10 minutes to brute-force crack a four character password
(26 characters, 4 letters = 26^4 = 456,976) on a 450MHz computer. Using
that as a guideline, it would take 8.25e92 minutes to crack a 56
character password. Even if you consider todays computers are 5-6 times
faster, dividing the following numbers by 5 doesn't make the picture any
prettier.

That is 1.93e91 hours, or
5.73e89 days, or
1.57e87 years...

>Add to that software firewalls on all LAN computers, access only to
>files only by particular usernames yadda yadda yadda. My hacking
>abilities are nil, so I find all of this stuff interesting.

Software firewalls on all LAN computers may or may not factor in here at
all, because they would normally be configured in such as manner that
access is allowed for LAN computers to resources that are needed. That
means, that if one computer shares files that other computers need, then
a hacker who has gained access to your LAN will be considered just
another LAN computer. However, there may be authentication involved, so
just having your computer on a LAN doesn't automatically give you rights
to read files on the network, so the hacker would also have another
obstacle of getting a valid username and password to actually gain
access to files...

Lars M. Hansen
http://www.hansenonline.net
(replace 'badnews' with 'news' in e-mail address)
Anonymous
a b F Wireless
November 12, 2004 6:49:10 PM

Archived from groups: alt.internet.wireless (More info?)

On Fri, 12 Nov 2004 08:12:35 -0500, Lars M. Hansen
<badnews@hansenonline.net> wrote:

>On Fri, 12 Nov 2004 11:19:47 +0000, Simon Pleasants spoketh

[WEP]

>Assuming there's enough activity, about 1 hour.

Really? That seems VERY quick. All previous posts I had read
suggested that it would take days to crack a 128bit WEP key. By 1hr,
did you mean just cracking the key AFTER all the packets had been
captured because surely on a low usage network like the one described
it would at least take days to capture enough information to have a go
at the key?

I am not disputing your figures, just surprised.

[WPA-PSK]

>Since it would be essentially brute force cracking, that would mean that
>they'd have to try every possible combination. Now, there's 26 letters
>and 52 counting upper case, plus 10 numbers and let's say 18 special
>characters just to make it easy on me ... With 56 characters, that would
>be 60^56, which is 3.77e99 combinations. According to my sources, Lopht
>takes about 10 minutes to brute-force crack a four character password
>(26 characters, 4 letters = 26^4 = 456,976) on a 450MHz computer. Using
>that as a guideline, it would take 8.25e92 minutes to crack a 56
>character password. Even if you consider todays computers are 5-6 times
>faster, dividing the following numbers by 5 doesn't make the picture any
>prettier.
>
>That is 1.93e91 hours, or
>5.73e89 days, or
>1.57e87 years...

Okay, it's the end of the working week for me and most of that went
straight over my head, but it sounds like a long time anyway.

>>Add to that software firewalls on all LAN computers, access only to
>>files only by particular usernames yadda yadda yadda. My hacking
>>abilities are nil, so I find all of this stuff interesting.
>
>Software firewalls on all LAN computers may or may not factor in here at
>all, because they would normally be configured in such as manner that
>access is allowed for LAN computers to resources that are needed.

In my case, because I know what the IP addresses are of the other
computers the software firewall on the server only allows access from
the two IP addresses used by the client machines. The hacker would
need to work out which IP addresses are allowed access. I understand
this information could be determined from the very same packets
captured to crack the key - as would the information necessary to
bypass the MAC address restrictions but will extend the time necessary
to compromise the system - even if only by minutes.

Furthermore, correct me if I am wrong, but the software firewall would
prevent any information being transmitted back from that machine, so
trying to take it over to send information out to the internet would
not work.

>means, that if one computer shares files that other computers need, then
>a hacker who has gained access to your LAN will be considered just
>another LAN computer. However, there may be authentication involved, so
>just having your computer on a LAN doesn't automatically give you rights
>to read files on the network, so the hacker would also have another
>obstacle of getting a valid username and password to actually gain
>access to files...

That's exactly it. Since only two users are ever likely to need
access to the server's resources the shares are available only to
those two and even then with increasing restrictions on the more
"interesting" files.
Anonymous
a b F Wireless
November 13, 2004 12:54:03 AM

Archived from groups: alt.internet.wireless (More info?)

On Fri, 12 Nov 2004 15:49:10 +0000, in alt.internet.wireless , Simon
Pleasants <plesbit@hotmail.com> wrote:

>On Fri, 12 Nov 2004 08:12:35 -0500, Lars M. Hansen
><badnews@hansenonline.net> wrote:
>
>>On Fri, 12 Nov 2004 11:19:47 +0000, Simon Pleasants spoketh
>
>[WEP]
>
>>Assuming there's enough activity, about 1 hour.
>
>Really? That seems VERY quick. All previous posts I had read
>suggested that it would take days to crack a 128bit WEP key.

There's a certain amount of FUD in the answer. Its true that using weak IVs
a cracker could penetrate the WEP key in an hour or so, provided he could
capture enough data traffic. Most home LANs don't generate enough, so its
likely to take days or longer. This is uneconomic for a cracker. Techniques
do exist to force your network to generate extra packets but again this is
more work. Its not really likely to be worth it to hack a 512K ADSL line.

>In my case, because I know what the IP addresses are of the other
>computers the software firewall on the server only allows access from
>the two IP addresses used by the client machines. The hacker would
>need to work out which IP addresses are allowed access.

Once they're through your encryption, this is trivial - the IP address is
in the header of every packet (it has to be, otherwise the recieving
machine couldn't send the reply back to the right box...).

>Furthermore, correct me if I am wrong, but the software firewall would
>prevent any information being transmitted back from that machine, so
>trying to take it over to send information out to the internet would
>not work.

You're wrong - your firewall is almost certainly configured to allow
machines on your local network to have normal access to each other. So any
machine masquerading as one of yours is in.

>That's exactly it. Since only two users are ever likely to need
>access to the server's resources the shares are available only to
>those two and even then with increasing restrictions on the more
>"interesting" files.

Yes, if you have another layer of security, eg NTFS permissioning, thats
good.

Security is like an Ogre remember.

--
Mark McIntyre
CLC FAQ <http://www.eskimo.com/~scs/C-faq/top.html&gt;
CLC readme: <http://www.ungerhu.com/jxh/clc.welcome.txt&gt;

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----
Anonymous
a b F Wireless
November 14, 2004 8:34:10 PM

Archived from groups: alt.internet.wireless (More info?)

On Fri, 12 Nov 2004 21:54:03 +0000, Mark McIntyre
<markmcintyre@spamcop.net> wrote:

>On Fri, 12 Nov 2004 15:49:10 +0000, in alt.internet.wireless , Simon
>Pleasants <plesbit@hotmail.com> wrote:
>
>>Furthermore, correct me if I am wrong, but the software firewall would
>>prevent any information being transmitted back from that machine, so
>>trying to take it over to send information out to the internet would
>>not work.
>
>You're wrong - your firewall is almost certainly configured to allow
>machines on your local network to have normal access to each other. So any
>machine masquerading as one of yours is in.

Well I'm not wrong - but I didn't word my question very well.

As you say, cracking a WEP key on a low volume network, such as mine, to
use a 512 DSL line is hardly worth it. Besides I use a gibberish 56
character WPA key anyway. But supposing someone thinks I'm worth the
effort and successfully cracks the encryption and then jumps the minor
hurdles of the MAC addresses and IP restrictions they can log into the
network. Once there they won't have any access to my files because they
are all stored within two or three master folders, each of which is shared,
but all "everybody" permissions have been removed and replaced simply with
access available only to the two usernames which will need access. Only
one of those actually has "full control", the other having read only, or
read-write access to some sub-folders and no access at all to others.

But supposing they'd even managed to capture enough information that they
can determine the username and the password of the network's master user
(i.e. me) then now they have the ability to access the files. The firewall
will not interfere with traffic from what is believed to be a recognised IP
address. It will, however, prevent anyone from trying to take control of
the machine to issue vast amounts of traffic out to the internet because
any trojans should be spotted by the AV and anything trying to transmit to
the internet will be blocked by ZA.
--
Simon Pleasants <plesbit@hotmail.com>
"Keep a dream in your pocket....
....never let it fade away"
Anonymous
a b F Wireless
November 14, 2004 11:07:46 PM

Archived from groups: alt.internet.wireless (More info?)

On Sun, 14 Nov 2004 17:34:10 +0000, in alt.internet.wireless , Simon
Pleasants <plesbit@hotmail.com> wrote:

>But supposing they'd even managed to capture enough information that they
>can determine the username and the password of the network's master user
>(i.e. me) then now they have the ability to access the files. The firewall
>will not interfere with traffic from what is believed to be a recognised IP
>address. It will, however, prevent anyone from trying to take control of
>the machine to issue vast amounts of traffic out to the internet because
>any trojans should be spotted by the AV and anything trying to transmit to
>the internet will be blocked by ZA.

But it won't - ZA is running on /your/ PC. The cracker will copy your stuff
to his pc, using standard windows protocols which you set ZA to permit.
Then he directly sends the stuff to the net from his own PC, but using your
router, or more likely downloads a zillion tons of illegal pron to his PC,
using your network.....

--
Mark McIntyre
CLC FAQ <http://www.eskimo.com/~scs/C-faq/top.html&gt;
CLC readme: <http://www.ungerhu.com/jxh/clc.welcome.txt&gt;

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----
Anonymous
a b F Wireless
November 15, 2004 12:23:25 PM

Archived from groups: alt.internet.wireless (More info?)

On Sun, 14 Nov 2004 20:07:46 +0000, Mark McIntyre
<markmcintyre@spamcop.net> wrote:

>On Sun, 14 Nov 2004 17:34:10 +0000, in alt.internet.wireless , Simon
>Pleasants <plesbit@hotmail.com> wrote:
>
>But it won't - ZA is running on /your/ PC. The cracker will copy your stuff
>to his pc, using standard windows protocols which you set ZA to permit.
>Then he directly sends the stuff to the net from his own PC, but using your
>router, or more likely downloads a zillion tons of illegal pron to his PC,
>using your network.....

Fair enough - but for that he would need to remain connected to my
network. As it does not extend beyond the end of my driveway or even
to the back of the back garden he'd have to be parked on my front lawn
to be able to use it. Of course he might be able to rig up a super
long distance antenna and connect to it but even that would be a fight
because there are countless other wireless networks eminating from
nearby houses and inevitably there are a lot of overlapping channels
in use.

But at the end of the day, why bother? First he'd have to locate my
network amongst all the others (several of which are unencrypted).
Then he'd have a crack a long gibberish WPA key. Then he'd have to
break into the server itself as all of the share permissions are very
tightly controlled and, having done all that, congratulations he now
has control of a single 512kbps ADSL line. Seems a lot of work for
very little reward. From my house alone I can detect six other AP's,
four of which use no encryption, the other two using WEP. Whilst I am
certainly not saying my network could never be compromised I believe
I've done enough to make it look a rather less attractive proposition
than some readily available alternatives.

I appreciate this conversation on the basis that the more you
understand about a potential threat the better equipped you are to do
something about it.
!