A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of specific fields in an LLDP frame. An attacker could exploit this vulnerability by sending a crafted LLDP packet to an interface of an affected device and having an authenticated user retrieve LLDP statistics from the affected device through CLI show commands or Simple Network Management Protocol (SNMP) requests. A successful exploit could allow the attacker to cause the LLDP service to crash and stop running on the affected device. In certain situations, the LLDP crash may result in a reload of the affected device. Note: LLDP is a Layer 2 link protocol. To exploit this vulnerability, an attacker would need to be directly connected to an interface of an affected device, either physically or logically (for example, through a Layer 2 Tunnel configured to transport the LLDP protocol).

A vulnerability in the Link Layer Discovery Protocol (LLDP) for Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, adjacent attacker to disable switching on a small form-factor pluggable (SFP) interface. This vulnerability is due to incomplete validation of the source of a received LLDP packet. An attacker could exploit this vulnerability by sending a crafted LLDP packet on an SFP interface to an affected device. A successful exploit could allow the attacker to disable switching on the SFP interface, which could disrupt network traffic.

A vulnerability in the Cisco Nexus 9000 Series Platform Leaf Switches for Application Centric Infrastructure (ACI) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on the affected device. This vulnerability affects Cisco Nexus 9000 Series Leaf Switches (TOR) - ACI Mode and Cisco Application Policy Infrastructure Controller (APIC). More Information: CSCuy93241. Known Affected Releases: 11.2(2x) 11.2(3x) 11.3(1x) 11.3(2x) 12.0(1x). Known Fixed Releases: 11.2(2i) 11.2(2j) 11.2(3f) 11.2(3g) 11.2(3h) 11.2(3l) 11.3(0.236) 11.3(1j) 11.3(2i) 11.3(2j) 12.0(1r).

Cisco IOS 12.0 through 15.6, Adaptive Security Appliance (ASA) Software 7.0.1 through 9.7.1.2, NX-OS 4.0 through 12.0, and IOS XE 3.6 through 3.18 are affected by a vulnerability involving the Open Shortest Path First (OSPF) Routing Protocol Link State Advertisement (LSA) database. This vulnerability could allow an unauthenticated, remote attacker to take full control of the OSPF Autonomous System (AS) domain routing table, allowing the attacker to intercept or black-hole traffic. The attacker could exploit this vulnerability by injecting crafted OSPF packets. Successful exploitation could cause the targeted router to flush its routing table and propagate the crafted OSPF LSA type 1 update throughout the OSPF AS domain. To exploit this vulnerability, an attacker must accurately determine certain parameters within the LSA database on the target router. This vulnerability can only be triggered by sending crafted unicast or multicast OSPF LSA type 1 packets. No other LSA type packets can trigger this vulnerability. OSPFv3 is not affected by this vulnerability. Fabric Shortest Path First (FSPF) protocol is not affected by this vulnerability. Cisco Bug IDs: CSCva74756, CSCve47393, CSCve47401.