https://qz.com/1103329/what-you-need-to-know-about-krack-the-newly-discovered-wifi-bug-that-lets-hackers-snoop-on-your-devices/

In a short YouTube video posted Monday (Oct. 16), security researcher Mathy Vanhoef demonstrated how a hacker could intercept data transmitted from a wireless device—in this case an Android phone—by exploiting a new flaw he discovered in wifi authentication. The hack takes about four minutes.

Vanhoef calls the hack KRACK, short for “key reinstallation attack,” and explained in a blog post that it can be used to read data transmitted between a device and the wireless network it’s connected to, even if that network is password-protected and encrypted. KRACK exploits a vulnerability in Wi-Fi Protected Access 2 (WPA2), the encryption protocol most consumers and many organizations use to protect their networks.