Wireless networks have been notoriously insecure since the early days of the 802.11b standard of the late 1990s. Since the standard’s inception, major 802.11 weaknesses, such as physical security weaknesses, encryption flaws, and authentication problems, have been discovered. Wireless attacks have been on the rise ever since.
The problem has gotten so bad that two wireless security standards have emerged to help fight back at the attackers: These standards have resolved many known security vulnerabilities of the 802.11a/b/g protocols. As with most security standards, the problem with these wireless security solutions is not that the solutions don’t work — it’s that many network administrators are resistant to change and don’t fully implement them.
Many administrators don’t want to reconfigure their existing wireless system sand don’t want to have to implement new security mechanisms for fear of making their networks more difficult to manage. These are legitimate concerns, but they leave many wireless networks vulnerable and waiting to be compromised.
Even after you have implemented WPA, WPA2, and the various other wireless protection techniques described in this book, your network may still be at risk. This can happen when (for example) employees install unsecured wireless access points or gateways on your network without you knowing about it. In our experience — even with all the wireless security standards and vendor solutions available — the majority of systems are still wide open to attack.
Bottom line: Ethical hacking isn’t a do-it-once-and-forget-it measure. It’s like an antivirus upgrade — you have to do it again from time to time.