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.

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.

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 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.

A vulnerability in the implementation of 802.11v Basic Service Set (BSS) Transition Management functionality in Cisco Wireless LAN Controllers 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 insufficient input validation of 802.11v BSS Transition Management Response packets that an affected device receives from wireless clients. An attacker could exploit this vulnerability by sending a malformed 802.11v BSS Transition Management Response packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload unexpectedly, resulting in a DoS condition. Cisco Bug IDs: CSCvb57803.

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 ISDN subsystem of Cisco IOS Software and Cisco IOS XE 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 insufficient input validation when the ISDN Q.931 messages are processed. An attacker could exploit this vulnerability by sending a malicious ISDN Q.931 message to an affected device. A successful exploit could allow the attacker to cause the process to crash, resulting in a reload of the affected device.

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.

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 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 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 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.

A vulnerability in the implementation of a protocol in Cisco Integrated Services Routers Generation 2 (ISR G2) Routers running Cisco IOS 15.0 through 15.6 could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to a misclassification of Ethernet frames. An attacker could exploit this vulnerability by sending a crafted Ethernet frame to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvc03809.

The DHCP Relay implementation in Cisco Adaptive Security Appliance (ASA) Software 8.4.7.29 and 9.1.7.4 allows remote attackers to cause a denial of service (interface wedge) via a crafted rate of DHCP packet transmission, aka Bug ID CSCuy66942.

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).

A vulnerability in Cisco IOS on Catalyst Switches and Nexus 9300 Series Switches could allow an unauthenticated, adjacent attacker to cause a Layer 2 network storm. More Information: CSCuu69332, CSCux07028. Known Affected Releases: 15.2(3)E. Known Fixed Releases: 12.2(50)SE4 12.2(50)SE5 12.2(50)SQ5 12.2(50)SQ6 12.2(50)SQ7 12.2(52)EY4 12.2(52)SE1 12.2(53)EX 12.2(53)SE 12.2(53)SE1 12.2(53)SE2 12.2(53)SG10 12.2(53)SG11 12.2(53)SG2 12.2(53)SG9 12.2(54)SG1 12.2(55)EX3 12.2(55)SE 12.2(55)SE1 12.2(55)SE10 12.2(55)SE2 12.2(55)SE3 12.2(55)SE4 12.2(55)SE5 12.2(55)SE6 12.2(55)SE7 12.2(55)SE8 12.2(55)SE9 12.2(58)EZ 12.2(58)SE1 12.2(58)SE2 12.2(60)EZ 12.2(60)EZ1 12.2(60)EZ2 12.2(60)EZ3 12.2(60)EZ4 12.2(60)EZ5 12.2(60)EZ6 12.2(60)EZ7 12.2(60)EZ8 15.0(1)EY2 15.0(1)SE 15.0(1)SE2 15.0(1)SE3 15.0(2)EA 15.0(2)EB 15.0(2)EC 15.0(2)ED 15.0(2)EH 15.0(2)EJ 15.0(2)EJ1 15.0(2)EK1 15.0(2)EX 15.0(2)EX1 15.0(2)EX3 15.0(2)EX4 15.0(2)EX5 15.0(2)EY 15.0(2)EY1 15.0(2)EY2 15.0(2)EZ 15.0(2)SE 15.0(2)SE1 15.0(2)SE2 15.0(2)SE3 15.0(2)SE4 15.0(2)SE5 15.0(2)SE6 15.0(2)SE7 15.0(2)SE9 15.0(2)SG10 15.0(2)SG3 15.0(2)SG6 15.0(2)SG7 15.0(2)SG8 15.0(2)SG9 15.0(2a)EX5 15.1(2)SG 15.1(2)SG1 15.1(2)SG2 15.1(2)SG3 15.1(2)SG4 15.1(2)SG5 15.1(2)SG6 15.2(1)E 15.2(1)E1 15.2(1)E2 15.2(1)E3 15.2(1)EY 15.2(2)E 15.2(2)E3 15.2(2b)E.

The Adaptive Wireless Intrusion Prevention System (wIPS) feature on Cisco Wireless LAN Controller (WLC) devices before 8.0.140.0, 8.1.x and 8.2.x before 8.2.121.0, and 8.3.x before 8.3.102.0 allows remote attackers to cause a denial of service (device restart) via a malformed wIPS packet, aka Bug ID CSCuz40263.

The rate-limit feature in the 802.11 protocol implementation on Cisco Aironet 1800, 2800, and 3800 devices with software before 8.2.121.0 and 8.3.x before 8.3.102.0 allows remote attackers to cause a denial of service (device reload) via crafted 802.11 frames, aka Bug ID CSCva06192.

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 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.

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 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 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.

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 Wireless LAN Controller (WLC) devices 7.4(121.0) and 8.0(0.30220.385) allow remote attackers to cause a denial of service via crafted wireless management frames, aka Bug ID CSCun92979.

Cisco Videoscape Session Resource Manager (VSRM) allows remote attackers to cause a denial of service (device restart) by sending a traffic flood to upstream devices, aka Bug ID CSCva01813.

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.

Cisco IOS 15.2(1)T1.11 and 15.2(2)TST allows remote attackers to cause a denial of service (device crash) via a crafted LLDP packet, aka Bug ID CSCun63132.

Cisco Wireless LAN Controller (WLC) devices with software 7.0(240.0), 7.3(101.0), and 7.4(1.19) allow remote attackers to cause a denial of service (device outage) by sending malformed 802.11i management data to a managed access point, aka Bug ID CSCub65236.

Cisco FirePOWER (formerly Sourcefire) 7000 and 8000 devices with software 5.4.0.1 allow remote attackers to cause a denial of service (inspection-engine outage) via crafted packets, aka Bug ID CSCuu10871.

Cisco IOS XE 16.1.1 allows remote attackers to cause a denial of service (device reload) via a packet with the 00-00-00-00-00-00 source MAC address, aka Bug ID CSCux48405.

Buffer overflow in Cisco NX-OS on Nexus 1000V devices for VMware vSphere 7.3(0)ZN(0.9); Nexus 3000 devices 6.0(2)U5(1.41), 7.0(3)I2(0.373), and 7.3(0)ZN(0.83); Nexus 4000 devices 4.1(2)E1(1b); Nexus 7000 devices 6.2(14)S1; Nexus 9000 devices 7.3(0)ZN(0.9); and MDS 9000 devices 6.2 (13) and 7.1(0)ZN(91.99) and MDS SAN-OS 7.1(0)ZN(91.99) allows remote attackers to cause a denial of service (device outage) via a crafted ARP packet, related to incorrect MTU validation, aka Bug IDs CSCuv71933, CSCuv61341, CSCuv61321, CSCuu78074, CSCut37060, CSCuv61266, CSCuv61351, CSCuv61358, and CSCuv61366.

Buffer overflow in Cisco NX-OS on Nexus 1000V devices for VMware vSphere 7.3(0)ZN(0.81), Nexus 3000 devices 7.3(0)ZN(0.81), Nexus 4000 devices 4.1(2)E1(1c), Nexus 7000 devices 7.2(0)N1(0.1), and Nexus 9000 devices 7.3(0)ZN(0.81) allows remote attackers to cause a denial of service (IGMP process restart) via a malformed IGMPv3 packet that is mishandled during memory allocation, aka Bug IDs CSCuv69713, CSCuv69717, CSCuv69723, CSCuv69732, and CSCuv48908.

Cisco Wireless LAN Controller (WLC) devices with software 7.5(102.0) and 7.6(1.62) allow remote attackers to cause a denial of service (device crash) by triggering an exception during attempted forwarding of unspecified IPv6 packets to a non-IPv6 device, aka Bug ID CSCuj01046.

Cisco Adaptive Security Appliance (ASA) Software 9.3(2) allows remote attackers to cause a denial of service (system reload) by sending crafted OSPFv2 packets on the local network, aka Bug ID CSCut52679.

The PPPoE establishment implementation in Cisco IOS XE 3.5.0S on ASR 1000 devices allows remote attackers to cause a denial of service (device reload) by sending malformed PPPoE Active Discovery Request (PADR) packets on the local network, aka Bug ID CSCty94202.

Cisco Adaptive Security Appliance (ASA) Software 9.3(2.243) and 100.13(0.21) allows remote attackers to cause a denial of service (device reload) by sending crafted OSPFv2 packets on the local network, aka Bug ID CSCus84220.

The Overlay Transport Virtualization (OTV) implementation in Cisco IOS XE 3.10S allows remote attackers to cause a denial of service (device reload) via a series of packets that are considered oversized and trigger improper fragmentation handling, aka Bug IDs CSCup37676 and CSCup30335.

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.

Cisco IOS 15.4S, 15.4SN, and 15.5S and IOS XE 3.13S and 3.14S allow remote attackers to cause a denial of service (device crash) by including an IA_NA option in a DHCPv6 Solicit message on the local network, aka Bug ID CSCur29956.

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.

The wireless web-authentication subsystem on Cisco Wireless LAN Controller (WLC) devices 7.5.x and 7.6.x before 7.6.120 allows remote attackers to cause a denial of service (process crash and device restart) via a crafted value, aka Bug ID CSCum03269.

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 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.