Wireless networks with open access points have become ubiquitous in the last few years. But as access has become more widely available the security of wireless networks has not come close to keeping pace. Researchers at Core Security will demonstrate a technique at Black Hat that enables an attacker to force a specific Cisco wireless access point to broadcast packets in WEP mode. The attack is specifically designed to work against the Cisco Aironet 1200 Series access points and is a twist on existing attacks that have shown WEP to be an eminently defeatable protocol. The researchers said that there is little Cisco can do about the problem, as it’s a function of the WEP protocol and the way that WPA migration mode works.
Source: https://threatpost.com/old-wireless-security-flaws-still-haunting-networks-072010/74233/