A vulnerability in the Cisco Network Plug and Play application of Cisco IOS 12.4 through 15.6 and Cisco IOS XE 3.3 through 16.4 could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data by using an invalid certificate. The vulnerability is due to insufficient certificate validation by the affected software. An attacker could exploit this vulnerability by supplying a crafted certificate to an affected device. A successful exploit could allow the attacker to conduct man-in-the-middle attacks to decrypt confidential information on user connections to the affected software. Cisco Bug IDs: CSCvc33171.

A vulnerability in motherboard console ports of line cards for Cisco ASR 1000 Series Aggregation Services Routers and Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, physical attacker to access an affected device's operating system. The vulnerability exists because an engineering console port is available on the motherboard of the affected line cards. An attacker could exploit this vulnerability by physically connecting to the console port on the line card. A successful exploit could allow the attacker to gain full access to the affected device's operating system. This vulnerability affects only Cisco ASR 1000 Series Routers that have removable line cards and Cisco cBR-8 Converged Broadband Routers, if they are running certain Cisco IOS XE 3.16 through 16.5 releases. Cisco Bug IDs: CSCvc65866, CSCve77132.

A vulnerability in the package unbundle utility of Cisco IOS XE Software could allow an authenticated, local attacker to gain write access to some files in the underlying operating system. This vulnerability affects the following products if they are running a vulnerable release of Cisco IOS XE Software: Cisco 5700 Series Wireless LAN Controllers, Cisco Catalyst 3650 Series Switches, Cisco Catalyst 3850 Series Switches, Cisco Catalyst 4500E Series Switches, Cisco Catalyst 4500X Series Switches. More Information: CSCva60013 CSCvb22622. Known Affected Releases: 3.7(0) 16.4.1 Denali-16.1.3 Denali-16.2.2 Denali-16.3.1. Known Fixed Releases: 15.2(4)E3 16.1(2.208) 16.2(2.42) 16.3(1.22) 16.4(0.190) 16.5(0.29).

The Neighbor Discovery (ND) protocol implementation in the IPv6 stack in Cisco IOS XE 2.1 through 3.17S, IOS XR 2.0.0 through 5.3.2, and NX-OS allows remote attackers to cause a denial of service (packet-processing outage) via crafted ND messages, aka Bug ID CSCuz66542, as exploited in the wild in May 2016.