A dangerous wireless security problem has been exposed in most laptops running a recent version of Windows at ShmooCon, the hacker conference held in Washington DC.
The laptop must be running Windows XP or 2000, have built-in wireless functionality and be unprotected by firewall software.

The flaw is based on how the operating system is configured to search for any available wireless connection when the laptop is started up. If no wireless link is found, Windows creates an ad-hoc "local link address", instead of a "private network".

The address becomes associated with the name of the last wireless network that provided the user with a real web address. Windows then causes the laptop to broadcast that network name to other computers in close range of the machine.

By creating a network connection on his laptop that matches the network name being broadcast by the target machine, the two laptops could communicate with each other on the same local link address. And the hacker effectively gets control of your laptop.
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