Fascinating report says high-power Wi-Fi adapter bundled with network key cracker: Owen Fletcher reports from China for the IDG News Service that kits are being sold for easy cracking of WEP/WPA-protected networks. Fletcher apparently bought one for about US$24 (¥165) at a bazaar, including setup help. The kit is a CD-ROM with software, a six-inch antenna and Wi-Fi adapter, and a live boot CD.
While WEP is easily cracked, sometimes in seconds, WPA requires a large precomputed set of keys in the terabytes. The reporter cracked a 40-bit WEP key ("sugar") in an hour, which is quite a while. That implies that the router had only strong initialization vectors and other improvements in WEP that typically only forestall cracking by minutes. (With weak IVs, a subset of the counters used to create separate keying material for each packet, an older or unpatched router's key could be broken in 30 seconds to about 5 minutes.)