An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).

Wi-Fi Protected Access (WPA and WPA2) that support 802.11v allows reinstallation of the Integrity Group Temporal Key (IGTK) when processing a Wireless Network Management (WNM) Sleep Mode Response frame, allowing an attacker within radio range to replay frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Station-To-Station-Link (STSL) Transient Key (STK) during the PeerKey handshake, allowing an attacker within radio range to replay, decrypt, or spoof frames.

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Tunneled Direct-Link Setup (TDLS) Peer Key (TPK) during the TDLS handshake, allowing an attacker within radio range to replay, decrypt, or spoof frames.

Wi-Fi Protected Access (WPA and WPA2) that supports IEEE 802.11w allows reinstallation of the Integrity Group Temporal Key (IGTK) during the group key handshake, allowing an attacker within radio range to spoof frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) that supports IEEE 802.11r allows reinstallation of the Pairwise Transient Key (PTK) Temporal Key (TK) during the fast BSS transmission (FT) handshake, allowing an attacker within radio range to replay, decrypt, or spoof frames.

Wi-Fi Protected Access (WPA and WPA2) that supports IEEE 802.11w allows reinstallation of the Integrity Group Temporal Key (IGTK) during the four-way handshake, allowing an attacker within radio range to spoof frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) that support 802.11v allows reinstallation of the Group Temporal Key (GTK) when processing a Wireless Network Management (WNM) Sleep Mode Response frame, allowing an attacker within radio range to replay frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Group Temporal Key (GTK) during the four-way handshake, allowing an attacker within radio range to replay frames from access points to clients.

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Group Temporal Key (GTK) during the group key handshake, allowing an attacker within radio range to replay frames from access points to clients.