The evolution of wireless security could at best be described as trial and error. The initial standard that debuted in the late 1990s — Wired Equivalent Privacy (WEP) — had significant security problems, and the first two version of Wireless Protected Access, WPA and WPA2, both have been found to be vulnerable to a variety of other security issues.

The trials continue with a host of so-called fragmentation attacks, or FragAttacks, that abuse the aggregation and fragmentation to allow machine-in-the-middle attacks. Details of the vulnerabilities, which have been kept secret for nine months, were disclosed at the Black Hat USA briefings on Aug. 5.