For today, each of us is using wireless communication capabilities. Almost anywhere in cities such as Moscow you can find an access point and access to the Internet. Often people use open access points in transport, parks, shopping centers or cafes. But in such cases, wireless network clients are particularly at risk of being attacked by intruders and losing personal data. This article discusses the security of wireless clients, as well as the vulnerability of wireless Wi-Fi networks. This vulnerability can be exploited as a result of the new library features for capturing network traffic named as libpcap. This library allows not only to intercept the traffic of wireless networks, but also to send packets to the network using the network ca...