A vulnerability in the Layer 2 punt code of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a queue wedge on an interface that receives specific Layer 2 frames, resulting in a denial of service (DoS) condition. This vulnerability is due to improper handling of certain Layer 2 frames. An attacker could exploit this vulnerability by sending specific Layer 2 frames on the segment the router is connected to. A successful exploit could allow the attacker to cause a queue wedge on the interface, resulting in a DoS condition.
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) support for the AutoReconnect feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to exhaust the free IP addresses from the assigned local pool. This vulnerability occurs because the code does not release the allocated IP address under certain failure conditions. An attacker could exploit this vulnerability by trying to connect to the device with a non-AnyConnect client. A successful exploit could allow the attacker to exhaust the IP addresses from the assigned local pool, which prevents users from logging in and leads to a denial of service (DoS) condition.
A vulnerability in Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a device to reload. The vulnerability is due to incorrect handling of certain valid, but not typical, Ethernet frames. An attacker could exploit this vulnerability by sending the Ethernet frames onto the Ethernet segment. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition.
A vulnerability in the Network Address Translation (NAT) Session Initiation Protocol (SIP) Application Layer Gateway (ALG) of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper processing of transient SIP packets on which NAT is performed on an affected device. An attacker could exploit this vulnerability by using UDP port 5060 to send crafted SIP packets through an affected device that is performing NAT for SIP packets. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.
A vulnerability in the 802.1x multiple-authentication (multi-auth) feature of Cisco IOS Software could allow an unauthenticated, adjacent attacker to bypass the authentication phase on an 802.1x multi-auth port. The vulnerability is due to a logic change error introduced into the code. An attacker could exploit this vulnerability by trying to access an 802.1x multi-auth port after a successful supplicant has authenticated. An exploit could allow the attacker to bypass the 802.1x access controls and obtain access to the network. Cisco Bug IDs: CSCvg69701.