Useless wireless security options.

[DreamerBrian]

So I read a lot about wireless security on the forum (just as we all do) and many people make the statement that certain security options for wireless are useless. For example: disabling SSID broadcast and MAC address filtering. I understand the point that those security options can be exploited but I do not understand how. Anyone care to explain how besides just "use a packet sniffer"?

Brian

 

[TiZakit]

MAC address spoofing gets around the MAC address thing.

 

[DreamerBrian]

OK so with MAC spoofing you use your packet sniffer to monitor the traffic > find the MAC address that is successfully communicating with the desired network > change the MAC address value of your NIC to match the MAC address value of the computer that is successfully communicating.

Easy enough in Linux because you only have to disable/re-enable the interface and change the address in the command line. I looked it up on Wikipedia and in W7 you have to change the value in the registry supposedly within the "NetworkAddress" value that is located in a subkey under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318} or you can download programs that do it for you.

Cool. Makes sense now. I wouldn't say that MAC address filtering is worthless because of the minimal amount of processing power that it requires. It would be a good measure to use in conjunction with other measures.

Brian

 

[petteyg359]

I understand the point that those security options can be exploited but I do not understand how. Anyone care to explain how besides just "use a packet sniffer"?

1. Anybody with a few brain cells and Wireshark can pull all your MAC addresses out of the air in five seconds. Every network transmission (whether wireless or not) includes the MAC address of the source.

2. If you set the router to not broadcast the SSID, then every client broadcasts it. "Hiding" the SSID effectively makes your network MORE visible. Also, when you take your laptop to the airport, it will still be probing for your home SSID. Somebody with a packet sniffer will see that, and set up a fake AP under that SSID. Your laptop will happily connect to it, and they'll eavesdrop on everything you do (unless you've set up the association with a specific MAC address; NetworkManager in Linux will allow adding an AP's MAC address to a network profile. That way it will only associate if both the SSID and MAC match, so that TSA d-bag won't be able to hi-jack your connection (he'll probably still steal your underwear, though)).

Cool. Makes sense now. I wouldn't say that MAC address filtering is worthless because of the minimal amount of processing power that it requires. It would be a good measure to use in conjunction with other measures.

No, it wouldn't. 1+0 is still only 1. Adding the zero is useless.

 

[DreamerBrian]

I didn't know that if you disabled SSID broadcast then all of the clients attempting to connect to that SSID advertise it in each request to connect. Good to know!