Cisco IOS XR 4.3(.2) and earlier on ASR 9000 devices does not properly perform NetFlow sampling of IP packets, which allows remote attackers to cause a denial of service (chip and card hangs) via malformed (1) IPv4 or (2) IPv6 packets, aka Bug ID CSCuo68417.

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 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 IOS XE on ASR1000 devices, when PPPoE termination is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed PPPoE packet, aka Bug ID CSCuo55180.

Cisco IOS XR does not properly throttle ICMPv6 redirect packets, which allows remote attackers to cause a denial of service (IPv4 and IPv6 transit outage) via crafted redirect messages, aka Bug ID CSCum14266.

A vulnerability in the UDP broadcast forwarding function of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability is due to improper handling of UDP broadcast packets that are forwarded to an IPv4 helper address. An attacker could exploit this vulnerability by sending multiple UDP broadcast packets to the affected device. An exploit could allow the attacker to cause a buffer leak on the affected device, eventually resulting in a DoS condition requiring manual intervention to recover. This vulnerability affects all Cisco IOS XR platforms running 6.3.1, 6.2.3, or earlier releases of Cisco IOS XR Software when at least one IPv4 helper address is configured on an interface of the device. Cisco Bug IDs: CSCvi35625.

A vulnerability in the Internet Group Management Protocol (IGMP) packet-processing functionality of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust buffers on an affected device, resulting in a denial of service (DoS) condition, aka a Memory Leak. The vulnerability is due to the affected software insufficiently processing IGMP Membership Query packets that are sent to an affected device. An attacker could exploit this vulnerability by sending a large number of IGMP Membership Query packets, which contain certain values, to an affected device. A successful exploit could allow the attacker to exhaust buffers on the affected device, resulting in a DoS condition that requires the device to be reloaded manually. This vulnerability affects: Cisco Catalyst 4500 Switches with Supervisor Engine 8-E, if they are running Cisco IOS XE Software Release 3.x.x.E and IP multicast routing is configured; Cisco devices that are running Cisco IOS XE Software Release 16.x, if IP multicast routing is configured. Cisco Bug IDs: CSCuw09295, CSCve94496.

A vulnerability in the 802.11 frame validation functionality of the Cisco Wireless LAN Controller (WLC) could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to incomplete input validation of certain 802.11 management information element frames that an affected device receives from wireless clients. An attacker could exploit this vulnerability by sending a malformed 802.11 management frame to an affected device. A successful exploit could allow the attacker to cause the affected device to reload unexpectedly, resulting in a DoS condition. This vulnerability affects only Cisco Wireless LAN Controllers that are running Cisco Mobility Express Release 8.5.103.0. Cisco Bug IDs: CSCvg07024.

A vulnerability in the Pong tool of Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software attempts to free the same area of memory twice. An attacker could exploit this vulnerability by sending a pong request to an affected device from a location on the network that causes the pong reply packet to egress both a FabricPath port and a non-FabricPath port. An exploit could allow the attacker to cause a dual or quad supervisor virtual port-channel (vPC) to reload. This vulnerability affects the following products when running Cisco NX-OS Software Release 7.2(1)D(1), 7.2(2)D1(1), or 7.2(2)D1(2) with both the Pong and FabricPath features enabled and the FabricPath port is actively monitored via a SPAN session: Cisco Nexus 7000 Series Switches and Cisco Nexus 7700 Series Switches. Cisco Bug IDs: CSCuv98660.

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 Cisco Discovery Protocol (formerly known as CDP) subsystem of devices running, or based on, Cisco NX-OS Software contain a vulnerability that could allow an unauthenticated, adjacent attacker to create a denial of service (DoS) condition. The vulnerability is due to a failure to properly validate certain fields within a Cisco Discovery Protocol message prior to processing it. An attacker with the ability to submit a Cisco Discovery Protocol message designed to trigger the issue could cause a DoS condition on an affected device while the device restarts. This vulnerability affects Firepower 4100 Series Next-Generation Firewall, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Director Switches, Nexus 1000V Series Switches, Nexus 1100 Series Cloud Services Platforms, Nexus 2000 Series Switches, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 3600 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvc89242, CSCve40943, CSCve40953, CSCve40965, CSCve40970, CSCve40978, CSCve40992, CSCve41000, CSCve41007.

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.

A vulnerability in the implementation of the cluster feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation when handling Cluster Management Protocol (CMP) messages. An attacker could exploit this vulnerability by sending a malicious CMP message to an affected device. A successful exploit could allow the attacker to cause the switch to crash and reload or to hang, resulting in a DoS condition. If the switch hangs it will not reboot automatically, and it will need to be power cycled manually to recover.

Multiple vulnerabilities in the Cisco Discovery Protocol and Link Layer Discovery Protocol (LLDP) implementations for Cisco IP Phone Series 68xx/78xx/88xx could allow an unauthenticated, adjacent attacker to execute code remotely or cause a reload of an affected IP phone. These vulnerabilities are due to missing checks when the IP phone processes a Cisco Discovery Protocol or LLDP packet. An attacker could exploit these vulnerabilities by sending a malicious Cisco Discovery Protocol or LLDP packet to the targeted IP phone. A successful exploit could allow the attacker to execute code on the affected IP phone or cause it to reload unexpectedly, resulting in a denial of service (DoS) condition.Note: Cisco Discovery Protocol 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).Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.

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 when an FCoE-related process unexpectedly reloads. This vulnerability affects Cisco NX-OS Software on the following Cisco devices when they are configured for FCoE: Multilayer Director Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches. More Information: CSCvc91729. Known Affected Releases: 8.3(0)CV(0.833). Known Fixed Releases: 8.3(0)ISH(0.62) 8.3(0)CV(0.944) 8.1(1) 8.1(0.8)S0 7.3(2)D1(0.47).

A vulnerability in the DECnet Phase IV and DECnet/OSI protocol processing of Cisco IOS XE 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 of DECnet traffic that is received by an affected device. An attacker could exploit this vulnerability by sending DECnet traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in the Cisco Discovery Protocol implementation for Cisco Video Surveillance 8000 Series IP Cameras could allow an unauthenticated, adjacent attacker to cause an affected IP camera to reload. The vulnerability is due to missing checks when Cisco Discovery Protocol messages are processed. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected IP camera. A successful exploit could allow the attacker to cause the affected IP camera to reload unexpectedly, resulting in a denial of service (DoS) condition. Note: Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

Cisco IOS 12.1T, 12.2, 12.2T, 12.3 and 12.3T, with Multi Protocol Label Switching (MPLS) installed but disabled, allows remote attackers to cause a denial of service (device reload) via a crafted packet sent to the disabled interface.

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.

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.

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.

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.

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.

A vulnerability in the Autonomic Networking feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause autonomic nodes of an affected system to reload, resulting in a denial of service (DoS) condition. More Information: CSCvd88936. Known Affected Releases: Denali-16.2.1 Denali-16.3.1.

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 Autonomic Networking Infrastructure (ANI) registrar feature of Cisco IOS Software (possibly 15.2 through 15.6) and Cisco IOS XE Software (possibly 3.7 through 3.18, and 16) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to incomplete input validation on certain crafted packets. An attacker could exploit this vulnerability by sending a crafted autonomic network channel discovery packet to a device that has all the following characteristics: (1) running a Cisco IOS Software or Cisco IOS XE Software release that supports the ANI feature; (2) configured as an autonomic registrar; (3) has a whitelist configured. An exploit could allow the attacker to cause the affected device to reload. Note: Autonomic networking should be configured with a whitelist. Do not remove the whitelist as a workaround. Cisco Bug IDs: CSCvc42717.

The Network Processing Unit (NPU) in the Cisco Wireless LAN Controller (WLC) before 3.2.193.5, 4.0.x before 4.0.206.0, and 4.1.x allows remote attackers on a local wireless network to cause a denial of service (loss of packet forwarding) via (1) crafted SNAP packets, (2) malformed 802.11 traffic, or (3) packets with certain header length values, aka Bug ID CSCsg36361.

The Network Processing Unit (NPU) in the Cisco Wireless LAN Controller (WLC) before 3.2.171.5, 4.0.x before 4.0.206.0, and 4.1.x allows remote attackers on a local wireless network to cause a denial of service (loss of packet forwarding) via (1) crafted SNAP packets, (2) malformed 802.11 traffic, or (3) packets with certain header length values, aka Bug IDs CSCsg15901 and CSCsh10841.

Unspecified vulnerability in Cisco IOS 12.2SXA, SXB, SXD, and SXF; and the MSFC2, MSFC2a and MSFC3 running in Hybrid Mode on Cisco Catalyst 6000, 6500 and Cisco 7600 series systems; allows remote attackers on a local network segment to cause a denial of service (software reload) via a certain MPLS packet.

The packet driver in Cisco IOS allows remote attackers to cause a denial of service (device reload) via a series of (1) Virtual Switching Systems (VSS) or (2) Bidirectional Forwarding Detection (BFD) packets, aka Bug IDs CSCug41049 and CSCue61890.

A vulnerability in the Open Shortest Path First version 3 (OSPFv3) implementation in Cisco IOS and IOS XE Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. The vulnerability is due to incorrect handling of specific OSPFv3 packets. An attacker could exploit this vulnerability by sending crafted OSPFv3 Link-State Advertisements (LSA) to an affected device. An exploit could allow the attacker to cause an affected device to reload, leading to a denial of service (DoS) condition.

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.

Multiple vulnerabilities in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition of an affected device. These vulnerabilities are due to insufficient validation of CAPWAP packets. An attacker could exploit these vulnerabilities by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.

A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

A vulnerability in the 802.11 association frame validation of Cisco Catalyst 9100 Series Access Points (APs) 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 certain parameters within association request frames received by the AP. An attacker could exploit this vulnerability by sending a crafted 802.11 association request to a nearby device. An exploit could allow the attacker to unexpectedly reload the device, resulting in a DoS condition.

A vulnerability in the Cisco Discovery Protocol of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an unauthenticated, adjacent attacker to cause a kernel panic on an affected system, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect processing of certain Cisco Discovery Protocol packets. An attacker could exploit this vulnerability by continuously sending certain Cisco Discovery Protocol packets to an affected device. A successful exploit could allow the attacker to cause a kernel panic on the system that is running the affected software, resulting in a DoS condition.

A vulnerability in the Cisco Discovery Protocol service of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause the service to restart, resulting in a denial of service (DoS) condition. This vulnerability is due to improper handling of Cisco Discovery Protocol messages that are processed by the Cisco Discovery Protocol service. An attacker could exploit this vulnerability by sending a series of malicious Cisco Discovery Protocol messages to an affected device. A successful exploit could allow the attacker to cause the Cisco Discovery Protocol service to fail and restart. In rare conditions, repeated failures of the process could occur, which could cause the entire device to restart.

A vulnerability in Simple Network Management Protocol (SNMP) trap generation for wireless clients of Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause an affected device to unexpectedly reload, resulting in a denial of service (DoS) condition on the device. This vulnerability is due to a lack of input validation of the information used to generate an SNMP trap related to a wireless client connection event. An attacker could exploit this vulnerability by sending an 802.1x packet with crafted parameters during the wireless authentication setup phase of a connection. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the bridge protocol data unit (BPDU) forwarding functionality of Cisco Aironet Access Points (APs) could allow an unauthenticated, adjacent attacker to cause an AP port to go into an error disabled state. The vulnerability occurs because BPDUs received from specific wireless clients are forwarded incorrectly. An attacker could exploit this vulnerability on the wireless network by sending a steady stream of crafted BPDU frames. A successful exploit could allow the attacker to cause a limited denial of service (DoS) attack because an AP port could go offline.

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 authentication functionality of 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 insufficient error validation. An attacker could exploit this vulnerability by sending crafted packets to an affected device. A successful exploit could allow the attacker to cause the wireless LAN controller to crash, resulting in a DoS condition. Note: This vulnerability affects only devices that have Federal Information Processing Standards (FIPS) mode enabled.

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 the implementation of the Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an unauthenticated attacker who is in the same IS–IS area to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of crafted IS–IS link-state protocol data units (PDUs). An attacker could exploit this vulnerability by sending a crafted link-state PDU to an affected system to be processed. A successful exploit could allow the attacker to cause all routers within the IS–IS area to unexpectedly restart the IS–IS process, resulting in a DoS condition. This vulnerability affects Cisco devices if they are running a vulnerable release of Cisco IOS XR Software earlier than Release 6.6.3 and are configured with the IS–IS routing protocol. Cisco has confirmed that this vulnerability affects both Cisco IOS XR 32-bit Software and Cisco IOS XR 64-bit Software.

A vulnerability in the implementation of Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an unauthenticated attacker who is in the same IS-IS area to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of IS–IS link-state protocol data units (PDUs). An attacker could exploit this vulnerability by sending specific link-state PDUs to an affected system to be processed. A successful exploit could allow the attacker to cause incorrect calculations used in the weighted remote shared risk link groups (SRLG) or in the IGP Flexible Algorithm. It could also cause tracebacks to the logs or potentially cause the receiving device to crash the IS–IS process, resulting in a DoS condition.

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.

A vulnerability in the 802.11r Fast Transition (FT) implementation for Cisco IOS Access Points (APs) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected interface. The vulnerability is due to a lack of complete error handling condition for client authentication requests sent to a targeted interface configured for FT. An attacker could exploit this vulnerability by sending crafted authentication request traffic to the targeted interface, causing the device to restart unexpectedly.

A vulnerability in the handling of Inter-Access Point Protocol (IAPP) messages by Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability exist because the software improperly validates input on fields within IAPP messages. An attacker could exploit the vulnerability by sending malicious IAPP messages to an affected device. A successful exploit could allow the attacker to cause the Cisco WLC Software to reload, resulting in a DoS condition. Software versions prior to 8.2.170.0, 8.5.150.0, and 8.8.100.0 are affected.

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.