Mist Security Advisory – Kr00k Attack & FAQ

What is this vulnerability?

Kr00k – formally known as CVE-2019-15126 – is a vulnerability in certain Broadcom Wi-Fi chipsets that allows unauthorized decryption of some WPA2-encrypted traffic. The vulnerability is a possible transmission of a few frames without proper MAC level encryption.

Impact of this vulnerability

The risk is limited to information exposure in the few data frames that can be decrypted by a hacker.This attack does not compromise the integrity of end to end (SSL) encryption that is common for sensitive exchanges.

This vulnerability does not enable any of the following:

  • discover the original security key
  • inject data frames
  • cause buffer overflows
  • corrupt memory
  • execute arbitrary code on the AP

Resolution for this vulnerability:

Resolution requires updates to both, mobile clients as well as the network infrastructure. For the Mist Access Points, Mist has patched this vulnerability in the firmware of all Mist access points – AP21, AP41, AP61 and AP43. BT11 is not impacted by this vulnerability. The release plan is as follows:


Release Version Platforms  Availability
0.3.15480 AP21, AP41, AP61 Available Now
0.5.17360 AP21, AP41, AP61 Available Now
0.6.18746 AP43 Available Now