According to experts WiMAX technology is still facing problems in security and also vulnerable to Denial-of-Service attacks, because there is no mechanism in place to specifically detect and discard repeated packets in the message. An attacker could repeat many messages, valid or not, in an attempt to interfere with the operation of the network. The impact of this type of attack can be very high, because it might affect the operation of the communication system within WiMAX Technology.
The risk is significant and that it might be sensible to employ a second line of defense against such an attack. Several weaknesses in privacy and key management (PKM) have also been discovered. PKM prevents eavesdropping and passive attacks by using hashed-message-authentication code and traffic-encryption keys (TEK). All key negotiation and data-encryption-key generation rely on the authorization key’s (AK) secret. The AK is generated by the base station, and the TEK is generated from the AK but only has a 2-bit identifier space, which is insufficient during the AK lifetime. (WiMAX Vision)
Regardless of good intentions for WiMAX security, there are a number of potential attacks open to attackers, including:
- Rogue Base Stations
- Denial of Service Attacks
- Man-in-the-Middle Attacks
- Network manipulation with spoofed management frames
The real test of WiMAX security will come when providers begin wide-scale network deployments, and researchers and attackers have access to service CPE equipment. Other attacks including WiMAX protocol blurring may enable attackers to further manipulate Base Stations (BS’s) or Subscriber Stations (SS’s). Until then, the security of WiMAX technology is limited to forecast. (Joshua Wright, 2006)