A new exploitation technique called key reinstallation attacks used to break Wi-Fi handshakes that negotiate session keys was discovered. These attacks target the Wi-Fi/WPA2 standard. An adversary can trick a vulnerable Access Point (AP) into reinstalling the pairwise key by retransmitted or replayed FT Reassociation Request. While reinstalling the already in-use key, the associated packet number (sometimes also called nonce) and receive replay counter is reset. This causes nonce reuse, voiding any security the underlying encryption protocol is supposed to provide. For example, it allows decryption or injection of frames, and enables an attacker to replay frames.
Acknowledgments: Name: CERT Upstream: Mathy Vanhoef (University of Leuven)
Created hostapd tracking bugs for this issue: Affects: fedora-all [bug 1502588] Created wpa_supplicant tracking bugs for this issue: Affects: fedora-all [bug 1502589]
External References: https://access.redhat.com/security/vulnerabilities/kracks https://w1.fi/security/2017-1/wpa-packet-number-reuse-with-replayed-messages.txt https://www.krackattacks.com/
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2017:2907 https://access.redhat.com/errata/RHSA-2017:2907
Statement: This issue did not affect the versions of wpa_supplicant as shipped with Red Hat Enterprise Linux 5 and 6. This issue affects the versions of wpa_supplicant as shipped with Red Hat Enterprise Linux 7.