Wireless DHCP Log question

[nijinsky]

I logged on to the router config to find a neighbour using my wireless signal a while back. I was using WPA2 security but hadnt set mac address filtering. I assume that is enough to stop this happening. Now when I check I often find two entries in the DHCP client log for the same machine. Why would either my laptop or PC show up with two ip addresses?
Any advice gratefully received, cheers.

 

[sweep]

I logged on to the router config to find a neighbour using my wireless signal a while back. I was using WPA2 security but hadnt set mac address filtering. I assume that is enough to stop this happening. Now when I check I often find two entries in the DHCP client log for the same machine. Why would either my laptop or PC show up with two ip addresses?
Any advice gratefully received, cheers.

He could have cloned your mac address to get past the filter.

 

[Simon Le Tom]

There should be a setting to limit the amount of connections, i.e only one at a time. If it has this option, enable it and see if you can gain access at different times in the day.

 

[sweep]

MAC address filtering is useless, as is hiding your SSID, changing your SSID from the default is defintely worthwhile though (makes the encrytion stronger). Do not use WEP, its easy to crack even with a strong passkey. Use WPA (2 if available) and use a strong password, random characters with no words like these (if you need to use it for more than one pc copy it onto a memory stick).

Do the above and your neighbour will find another target.

Elcomsoft claimed its Password Recovery product, which can also be used in a distributed fashion across a network for faster cracks, could speed up WPA/WPA2 passphrase guessing by a factor of 100. But what did that mean in practical terms? How long a passphrase and how fast to crack it?

I got an answer from Elcomsoft's Andrey Belenko, who said via e-mail that without dictionary words being involved, cracking is still quite intensive: perhaps three months to crack a lowercase-only random eight-character password using a PC with two Nvidia GTX 280 video cards. That's on the order of what seems reasonable, given the underlying algorithm's strength. There are 200 billion possible passphrases in this format, and some substantial hashing overhead to turn a passphrase into the WPA/WPA2 key material.

 

[auction294]

Unless you live next door to a geek then disabling the SSID and applying MAC address filtering is usually sufficient protection for any home network (obviously along with WPA).

If you're still then worried, and assuming a software firewall is also setup correctly then the only other solution I would suggest is calling to visit your neighbour and kicking his fucking head in.

...seriously, if this fucker can still hack in then have a word or get yourself a router than can offer better protection. Netgear DG834G is a reliable and feature packed router, pretty cheap as well. Other than that get a Linux box as a hardware firewall running something like Smoothwall which would keep the dick out.

 

[sweep]

Unless you live next door to a geek then disabling the SSID and applying MAC address filtering is usually sufficient protection for any home network (obviously along with WPA).

If you're still then worried, and assuming a software firewall is also setup correctly then the only other solution I would suggest is calling to visit your neighbour and kicking his fucking head in.

...seriously, if this fucker can still hack in then have a word or get yourself a router than can offer better protection. Netgear DG834G is a reliable and feature packed router, pretty cheap as well. Other than that get a Linux box as a hardware firewall running something like Smoothwall which would keep the dick out.

Thats a myth, it would only stop casual passers by connecting to an unsecured network, once a password is set they would give no additional protection..

 

[auction294]

No it's not a myth. That's your opinion. What I actually said was by disabling the SSID and applying MAC address filter that is usually sufficient for the home network. If we were to conduct a poll of any street in Greater Manchester with 100 houses and you were to ask the occupants "what is the SSID of your wireless connection?" then I would say at least 90% of the respondants would look back blankly at you. Without knowing what the SSID actually is, and does these people would not be able to employ any use of it. Then there is the MAC address filter. As practically all preconfigured wireless routers have WEP or WPA enabled as standard (Talk Talk, BT, etc) and these same routers do not have MAC filtering in place then again I will stand by my post that the two options are more than sufficient for the home network. Unless your neighour has sufficient networking knowledge and skills to make use of a wireless setup without these features then even WEP is more than enough.

I do this all day everyday for a living, and have yet to come across any home network compromised when both these features are enabled, and in 99.9% of home networks it is us that turn these on.

 

[sweep]

No it's not a myth. That's your opinion. What I actually said was by disabling the SSID and applying MAC address filter that is usually sufficient for the home network. If we were to conduct a poll of any street in Greater Manchester with 100 houses and you were to ask the occupants "what is the SSID of your wireless connection?" then I would say at least 90% of the respondants would look back blankly at you. Without knowing what the SSID actually is, and does these people would not be able to employ any use of it. Then there is the MAC address filter. As practically all preconfigured wireless routers have WEP or WPA enabled as standard (Talk Talk, BT, etc) and these same routers do not have MAC filtering in place then again I will stand by my post that the two options are more than sufficient for the home network. Unless your neighour has sufficient networking knowledge and skills to make use of a wireless setup without these features then even WEP is more than enough.

I do this all day everyday for a living, and have yet to come across any home network compromised when both these features are enabled, and in 99.9% of home networks it is us that turn these on.

See the OP.
If someone has the tools (there are many and they're easily available, for example: <a class="postlink" href="http://www.remote-exploit.org/backtrack.html" onclick="window.open(this.href);return false;">http://www.remote-exploit.org/backtrack.html</a> ) and knowledge to crack a weak wpa passkey (wep is insecure even with a strong passkey) then mac filtering/hiding SSID will present no obstacle to them.

 

[auction294]

If someone has the tools (there are many and they're easily available, for example: <a class="postlink" href="http://www.remote-exploit.org/backtrack.html" onclick="window.open(this.href);return false;">http://www.remote-exploit.org/backtrack.html</a> ) and knowledge to crack a weak wpa passkey (wep is insecure even with a strong passkey) then mac filtering/hiding SSID will present no obstacle to them.

That was my point, your average Joe Public will not be able to do this, therefore your average home network is more than secure with these in place. Whatever is in place security wise will not be hack proof, McKinnon is living proof of this. However to expect home users to use Enterprise Class Firewalls or Routers is not feasable, neither is it reasonable to expect the public to have the skills or knowledge to setup a proper hardware firewall or pay someone to do so.

OP > PM me and I'll see what we can do with your router

 

[markbmcfc]

I logged on to the router config to find a neighbour using my wireless signal a while back. I was using WPA2 security but hadnt set mac address filtering. I assume that is enough to stop this happening. Now when I check I often find two entries in the DHCP client log for the same machine. Why would either my laptop or PC show up with two ip addresses?
Any advice gratefully received, cheers.

Ever plug your laptop in using Ethernet whilst having your wireless switched on? That would give you two IP's.