Cisco IOS 15.0(2)SG5, 15.1(2)SG3, 15.2(1)E, 15.3(3)S, and 15.4(1.13)S allows remote attackers to cause a denial of service (device crash) via a crafted LLDP packet, aka Bug ID CSCun66735.

Cisco Nexus 1000v Application Virtual Switch (AVS) devices before 5.2(1)SV3(1.5i) allow remote attackers to cause a denial of service (ESXi hypervisor crash and purple screen) via a crafted Cisco Discovery Protocol packet that triggers an out-of-bounds memory access, aka Bug ID CSCuw57985.

A vulnerability in the Fibre Channel over Ethernet (FCoE) protocol implementation in Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to an incorrect allocation of an internal interface index. An adjacent attacker with the ability to submit a crafted FCoE packet that crosses affected interfaces could trigger this vulnerability. A successful exploit could allow the attacker to cause a packet loop and high throughput on the affected interfaces, resulting in a DoS condition. This vulnerability has been fixed in version 7.3(5)N1(1).

A vulnerability in the Cisco Discovery Protocol or Link Layer Discovery Protocol (LLDP) implementation for the Cisco IP Phone 7800 and 8800 Series could allow an unauthenticated, adjacent attacker to cause an affected phone to reload unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability is due to missing length validation of certain Cisco Discovery Protocol or LLDP packet header fields. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol or LLDP packet to the targeted phone. A successful exploit could allow the attacker to cause the affected phone to reload unexpectedly, resulting in a temporary DoS condition. Versions prior to 12.6(1)MN80 are affected.

The IPv6 implementation in Cisco NX-OS does not properly handle neighbor-table adjacencies, which allows remote attackers to cause a denial of service (NS processing outage) via a series of malformed packets, aka Bug ID CSCtd15904.

The mDNS snooping functionality on Cisco Wireless LAN Controller (WLC) devices with software 7.4.1.54 and earlier does not properly manage buffers, which allows remote authenticated users to cause a denial of service (device reload) via crafted mDNS packets, aka Bug ID CSCue04153.

The Ethernet frame-forwarding implementation in Cisco NX-OS on Nexus 7000 devices allows remote attackers to cause a denial of service (forwarding loop and service outage) via a crafted frame, aka Bug ID CSCug47098.

A vulnerability in the HTTP-based client profiling feature of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of received traffic. An attacker could exploit this vulnerability by sending crafted traffic through a wireless access point. A successful exploit could allow the attacker to cause CPU utilization to increase, which could result in a DoS condition on an affected device and could cause new wireless client associations to fail. Once the offending traffic stops, the affected system will return to an operational state and new client associations will succeed.

Cisco ASR 1000 devices with software before 3.8S, when BDI routing is enabled, allow remote attackers to cause a denial of service (device reload) via crafted (1) broadcast or (2) multicast ICMP packets with fragmentation, aka Bug ID CSCub55948.

A vulnerability in Cisco access point (AP) software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of certain parameters within 802.11 frames. An attacker could exploit this vulnerability by sending a wireless 802.11 association request frame with crafted parameters to an affected device. A successful exploit could allow the attacker to cause an unexpected reload of an affected device, resulting in a DoS condition.

The HTTP Profiler on the Cisco Aironet Access Point with software 15.2 and earlier does not properly manage buffers, which allows remote attackers to cause a denial of service (device reload) via crafted HTTP requests, aka Bug ID CSCuc62460.

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco NX-OS Software for the Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, adjacent attacker to cause the IS-IS process to unexpectedly restart, which could cause an affected device to reload. This vulnerability is due to insufficient input validation when parsing an ingress IS-IS packet. An attacker could exploit this vulnerability by sending a crafted IS-IS packet to an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition due to the unexpected restart of the IS-IS process, which could cause the affected device to reload. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2 adjacent to the affected device.

Unspecified vulnerability in Cisco IOS 12.2SRE before 12.2(33)SRE4, 15.0, and 15.1, and IOS XE 2.1.x through 3.3.x, when an MPLS domain is configured, allows remote attackers to cause a denial of service (device crash) via a crafted IPv6 packet, related to an expired MPLS TTL, aka Bug ID CSCto07919.

Cisco NX-OS 5.2 and 6.1 on Nexus 7000 series switches allows remote attackers to cause a denial of service (process crash or packet loss) via a large number of ARP packets, aka Bug ID CSCtr44822.

dot11t/t_if_dot11_hal_ath.c in Cisco IOS 12.3, 12.4, 15.0, and 15.1 allows remote attackers to cause a denial of service (assertion failure and reboot) via 802.11 wireless traffic, as demonstrated by a video call from Apple iOS 5.0 on an iPhone 4S, aka Bug ID CSCtt94391.

Cisco IOS before 15.1(1)SY on ASR 1000 devices, when Multicast Listener Discovery (MLD) tracking is enabled for IPv6, allows remote attackers to cause a denial of service (device reload) via crafted MLD packets, aka Bug ID CSCtz28544.

A vulnerability in the IPv6 protocol handling of the management interfaces of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause an IPv6 flood on the management interface network of an affected device. The vulnerability exists because the software incorrectly forwards IPv6 packets that have an IPv6 node-local multicast group address destination and are received on the management interfaces. An attacker could exploit this vulnerability by connecting to the same network as the management interfaces and injecting IPv6 packets that have an IPv6 node-local multicast group address destination. A successful exploit could allow the attacker to cause an IPv6 flood on the corresponding network. Depending on the number of Cisco IOS XR Software nodes on that network segment, exploitation could cause excessive network traffic, resulting in network degradation or a denial of service (DoS) condition.

A vulnerability in the Layer 2 punt code of Cisco IOS XR Software running on Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to cause the affected line card to reboot. This vulnerability is due to incorrect handling of specific Ethernet frames that cause a spin loop that can make the network processors unresponsive. An attacker could exploit this vulnerability by sending specific types of Ethernet frames on the segment where the affected line cards are attached. A successful exploit could allow the attacker to cause the affected line card to reboot.

A vulnerability in the WLAN Control Protocol (WCP) implementation for Cisco Aironet Access Point (AP) software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect error handling when an affected device receives an unexpected 802.11 frame. An attacker could exploit this vulnerability by sending certain 802.11 frames over the wireless network to an interface on an affected AP. A successful exploit could allow the attacker to cause a packet buffer leak. This could eventually result in buffer allocation failures, which would trigger a reload of the affected device.

A vulnerability in the Link Layer Discovery Protocol (LLDP) implementation for the Cisco Video Surveillance 7000 Series IP Cameras firmware could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper management of memory resources, referred to as a double free. An attacker could exploit this vulnerability by sending crafted LLDP packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: LLDP is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

A vulnerability in the Link Layer Discovery Protocol (LLDP) feature for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, adjacent attacker to cause a memory leak, which could result in an unexpected reload of the device. This vulnerability is due to incorrect error checking when parsing ingress LLDP packets. An attacker could exploit this vulnerability by sending a steady stream of crafted LLDP packets to an affected device. A successful exploit could allow the attacker to cause a memory leak, which could result in a denial of service (DoS) condition when the device unexpectedly reloads. Note: This vulnerability cannot be exploited by transit traffic through the device. The crafted LLDP packet must be targeted to a directly connected interface, and the attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent). In addition, the attack surface for this vulnerability can be reduced by disabling LLDP on interfaces where it is not required.

A vulnerability in Cisco ASR 903 or ASR 920 Series Devices running with an RSP2 card could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on a targeted system because of incorrect IPv6 Packet Processing. More Information: CSCuy94366. Known Affected Releases: 15.4(3)S3.15. Known Fixed Releases: 15.6(2)SP 15.6(1.31)SP.

A vulnerability in the Ethernet packet handling of Cisco Aironet Access Points (APs) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by connecting as a wired client to the Ethernet interface of an affected device and sending a series of specific packets within a short time frame. A successful exploit could allow the attacker to cause a NULL pointer access that results in a reload of the affected device.

A vulnerability in the integrated wireless access point (AP) packet processing of the Cisco 1000 Series Connected Grid Router (CGR1K) could allow an unauthenticated, adjacent attacker to cause a denial of service condition on an affected device. This vulnerability is due to insufficient input validation of received traffic. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to cause the integrated AP to stop processing traffic, resulting in a DoS condition. It may be necessary to manually reload the CGR1K to restore AP operation.

A vulnerability in Cisco IOS XE Wireless Controller Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of access point (AP) Cisco Discovery Protocol (CDP) neighbor reports when they are processed by the wireless controller. An attacker could exploit this vulnerability by sending a crafted CDP packet to an AP. A successful exploit could allow the attacker to cause an unexpected reload of the wireless controller that is managing the AP, resulting in a DoS condition that affects the wireless network.

A vulnerability in the Switch Integrated Security Features (SISF) of Cisco IOS Software, Cisco IOS XE Software, Cisco NX-OS Software, and Cisco Wireless LAN Controller (WLC) AireOS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to the incorrect handling of DHCPv6 packets. An attacker could exploit this vulnerability by sending a crafted DHCPv6 packet to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the handling of specific packets that are punted from a line card to a route processor in Cisco IOS XR Software Release 7.9.2 could allow an unauthenticated, adjacent attacker to cause control plane traffic to stop working on multiple Cisco IOS XR platforms.  This vulnerability is due to incorrect handling of packets that are punted to the route processor. An attacker could exploit this vulnerability by sending traffic, which must be handled by the Linux stack on the route processor, to an affected device. A successful exploit could allow the attacker to cause control plane traffic to stop working, resulting in a denial of service (DoS) condition.

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) feature of Cisco NX-OS Software for Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, adjacent attacker to cause the IS-IS process to unexpectedly restart, which could cause an affected device to reload. This vulnerability is due to insufficient input validation when parsing an ingress IS-IS packet. An attacker could exploit this vulnerability by sending a crafted IS-IS packet to an affected device. A successful exploit could allow the attacker to cause the unexpected restart of the IS-IS process, which could cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device.

A vulnerability in the Cisco Express Forwarding functionality of Cisco IOS XE Software for Cisco ASR 903 Aggregation Services Routers with Route Switch Processor 3 (RSP3C) could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper memory management when Cisco IOS XE Software is processing Address Resolution Protocol (ARP) messages. An attacker could exploit this vulnerability by sending crafted ARP messages at a high rate over a period of time to an affected device. A successful exploit could allow the attacker to exhaust system resources, which eventually triggers a reload of the active route switch processor (RSP). If a redundant RSP is not present, the router reloads.

A vulnerability in the health monitoring diagnostics of Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, adjacent attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of specific Ethernet frames. An attacker could exploit this vulnerability by sending a sustained rate of crafted Ethernet frames to an affected device. A successful exploit could allow the attacker to cause the device to reload.

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).

The Cisco Wireless LAN Controller (WLC), Cisco Catalyst 6500 Wireless Services Module (WiSM), and Cisco Catalyst 3750 Integrated Wireless LAN Controller with software 4.x before 4.2.176.0 and 5.x before 5.2 allow remote attackers to cause a denial of service (web authentication outage or device reload) via unspecified network traffic, as demonstrated by a vulnerability scanner.

A vulnerability in the Wireless Network Control daemon (wncd) of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent wireless attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper memory management. An attacker could exploit this vulnerability by sending a series of IPv6 network requests from an associated wireless IPv6 client to an affected device. To associate a client to a device, an attacker may first need to authenticate to the network, or associate freely in the case of a configured open network. A successful exploit could allow the attacker to cause the wncd process to consume available memory and eventually cause the device to stop responding, resulting in a DoS condition.

The LLDP implementation in Cisco IOS allows remote attackers to cause a denial of service (device reload) via a malformed packet, aka Bug ID CSCum96282.

Cisco Adaptive Security Appliance (ASA) Software, when DHCPv6 replay is configured, allows remote attackers to cause a denial of service (device reload) via a crafted DHCPv6 packet, aka Bug ID CSCun45520.

The IP Device Tracking (IPDT) feature in Cisco IOS and IOS XE allows remote attackers to cause a denial of service (IPDT AVL corruption and device reload) via a crafted sequence of ARP packets, aka Bug ID CSCuh38133.

A vulnerability in the PPP over Ethernet (PPPoE) termination feature of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to crash the ppp_ma process, resulting in a denial of service (DoS) condition. This vulnerability is due to the improper handling of malformed PPPoE packets that are received on a router that is running Broadband Network Gateway (BNG) functionality with PPPoE termination on a Lightspeed-based or Lightspeed-Plus-based line card. An attacker could exploit this vulnerability by sending a crafted PPPoE packet to an affected line card interface that does not terminate PPPoE. A successful exploit could allow the attacker to crash the ppp_ma process, resulting in a DoS condition for PPPoE traffic across the router.

A vulnerability in the segment routing feature for the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending specific IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process on all affected devices that are participating in the Flexible Algorithm to crash and restart, resulting in a DoS condition. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and must have formed an adjacency. This vulnerability affects segment routing for IS-IS over IPv4 and IPv6 control planes as well as devices that are configured as level 1, level 2, or multi-level routing IS-IS type.

A vulnerability in the handling of specific Ethernet frames by Cisco IOS XR Software for various Cisco Network Convergence System (NCS) platforms could allow an unauthenticated, adjacent attacker to cause critical priority packets to be dropped, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect classification of certain types of Ethernet frames that are received on an interface. An attacker could exploit this vulnerability by sending specific types of Ethernet frames to or through the affected device. A successful exploit could allow the attacker to cause control plane protocol relationships to fail, resulting in a DoS condition. For more information, see the section of this advisory. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation when parsing an ingress IS-IS packet. An attacker could exploit this vulnerability by sending a crafted IS-IS packet to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and have formed an adjacency.

A vulnerability in Cisco IOS Software for Cisco Catalyst 6000 Series Switches could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly. This vulnerability is due to improper handling of process-switched traffic. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the handling of encrypted wireless frames of Cisco Aironet Access Point (AP) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on the affected device. This vulnerability is due to incomplete cleanup of resources when dropping certain malformed frames. An attacker could exploit this vulnerability by connecting as a wireless client to an affected AP and sending specific malformed frames over the wireless connection. A successful exploit could allow the attacker to cause degradation of service to other clients, which could potentially lead to a complete DoS condition.

The ISDN implementation in Cisco IOS 15.3S allows remote attackers to cause a denial of service (device reload) via malformed Q931 SETUP messages, aka Bug ID CSCut37890.

A vulnerability in the OSPF version 2 (OSPFv2) feature of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of OSPF updates that are processed by a device. An attacker could exploit this vulnerability by sending a malformed OSPF update to the device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in the Layer 2 Ethernet services of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the line card network processor to reset, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of specific Ethernet frames that are received on line cards that have the Layer 2 services feature enabled. An attacker could exploit this vulnerability by sending specific Ethernet frames through an affected device. A successful exploit could allow the attacker to cause the ingress interface network processor to reset, resulting in a loss of traffic over the interfaces that are supported by the network processor. Multiple resets of the network processor would cause the line card to reset, resulting in a DoS condition.

A vulnerability in the multicast DNS (mDNS) gateway feature of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper management of mDNS client entries. An attacker could exploit this vulnerability by connecting to the wireless network and sending a continuous stream of specific mDNS packets. A successful exploit could allow the attacker to cause the wireless controller to have high CPU utilization, which could lead to access points (APs) losing their connection to the controller and result in a DoS condition.

A vulnerability in the ingress packet processing path of Cisco Firepower Threat Defense (FTD) Software for interfaces that are configured either as Inline Pair or in Passive mode could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation when Ethernet frames are processed. An attacker could exploit this vulnerability by sending malicious Ethernet frames through an affected device. A successful exploit could allow the attacker do either of the following: Fill the /ngfw partition on the device: A full /ngfw partition could result in administrators being unable to log in to the device (including logging in through the console port) or the device being unable to boot up correctly. Note: Manual intervention is required to recover from this situation. Customers are advised to contact the Cisco Technical Assistance Center (TAC) to help recover a device in this condition. Cause a process crash: The process crash would cause the device to reload. No manual intervention is necessary to recover the device after the reload.

A vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software, Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. This vulnerability is due to improper input validation of the UDLD packets. An attacker could exploit this vulnerability by sending specifically crafted UDLD packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. An attacker must have full control of a directly connected device. On Cisco IOS XR devices, the impact is limited to the reload of the UDLD process.