A vulnerability in the Tool Command Language (Tcl) interpreter of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, local attacker with privileged EXEC credentials to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient input validation of data passed to the Tcl interpreter. An attacker could exploit this vulnerability by executing crafted Tcl arguments on an affected device. An exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in the Hot Standby Router Protocol (HSRP) subsystem of Cisco IOS and IOS XE Software could allow an unauthenticated, adjacent attacker to receive potentially sensitive information from an affected device. The vulnerability is due to insufficient memory initialization. An attacker could exploit this vulnerability by receiving HSRPv2 traffic from an adjacent HSRP member. A successful exploit could allow the attacker to receive potentially sensitive information from the adjacent device.

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.

Cisco IOS XR through 5.3.2 mishandles Local Packet Transport Services (LPTS) flow-base entries, which allows remote attackers to cause a denial of service (session drop) by making many connection attempts to open TCP ports, aka Bug ID CSCux95576.

Cisco IOS XR through 4.3.2 on Gigabit Switch Router (GSR) 12000 devices does not properly check for a Bidirectional Forwarding Detection (BFD) header in a UDP packet, which allows remote attackers to cause a denial of service (line-card restart) via a crafted packet, aka Bug ID CSCuw56900.

Cisco IOS XR 5.1 and earlier allows remote attackers to cause a denial of service (process reload) via a malformed RSVP packet, aka Bug ID CSCuq12031.

Cisco IOS XR 5.1 and earlier on Network Convergence System 6000 devices allows remote attackers to cause a denial of service (NPU and card hang or reload) via a malformed MPLS packet, aka Bug ID CSCuq10466.

tacacsd in Cisco IOS XR 5.1 and earlier allows remote attackers to cause a denial of service (process reload) via a malformed TACACS+ packet, aka Bug ID CSCum00468.

snmpd in Cisco IOS XR 5.1 and earlier allows remote authenticated users to cause a denial of service (process reload) via a malformed SNMPv2 packet, aka Bug ID CSCun67791.

Unspecified vulnerability in the sshd_child_handler process in the SSH server in Cisco IOS XR 3.4.1 through 3.7.0 allows remote attackers to cause a denial of service (process crash and memory consumption) via a crafted SSH2 packet, aka Bug ID CSCsu10574.