Cisco IOS 15.2(3)E and earlier and IOS XE 3.6(2)E and earlier allow remote attackers to cause a denial of service (functionality loss) via crafted Cisco Discovery Protocol (CDP) packets, aka Bug ID CSCuu25770.

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 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 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.

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 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 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 Multiprotocol Label Switching (MPLS) Operations, Administration, and Maintenance (OAM) implementation of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to the incorrect handling of certain MPLS OAM packets. An attacker could exploit this vulnerability by sending malicious MPLS OAM packets to an affected device. A successful exploit could allow the attacker to cause the lspv_server process to crash. The crash could lead to system instability and the inability to process or forward traffic though the device, resulting in a DoS condition that require manual intervention to restore normal operating conditions.

A vulnerability in the Cluster Management Protocol (CMP) processing code in 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 insufficient input validation when processing CMP management packets. An attacker could exploit this vulnerability by sending malicious CMP management packets to an affected device. A successful exploit could cause the switch to crash, resulting in a DoS condition. The switch will reload automatically.

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 Border Gateway Patrol (BGP) Multiprotocol Label Switching (MPLS)-based Ethernet VPN (EVPN) implementation of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs when the affected software processes specific EVPN routing information. An attacker could exploit this vulnerability by injecting malicious traffic patterns into the targeted EVPN network. A successful exploit could result in a crash of the l2vpn_mgr process on Provider Edge (PE) device members of the same EVPN instance (EVI). On each of the affected devices, a crash could lead to system instability and the inability to process or forward traffic through the device, resulting in a DoS condition that would require manual intervention to restore normal operating conditions.

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 Easy Virtual Switching System (VSS) of Cisco IOS XE Software on Catalyst 4500 Series Switches could allow an unauthenticated, adjacent attacker to cause the switches to reload. The vulnerability is due to incomplete error handling when processing Cisco Discovery Protocol (CDP) packets used with the Easy Virtual Switching System. An attacker could exploit this vulnerability by sending a specially crafted CDP packet. An exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the ingress traffic validation of Cisco IOS XE Software for Cisco Aggregation Services Router (ASR) 900 Route Switch Processor 3 (RSP3) could allow an unauthenticated, adjacent attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability exists because the software insufficiently validates ingress traffic on the ASIC used on the RSP3 platform. An attacker could exploit this vulnerability by sending a malformed OSPF version 2 (OSPFv2) message to an affected device. A successful exploit could allow the attacker to cause a reload of the iosd process, triggering a reload of the affected device and resulting in a DoS condition.

A vulnerability in the Fibre Channel over Ethernet (FCoE) N-port Virtualization (NPV) protocol implementation in Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to an incorrect processing of FCoE packets when the fcoe-npv feature is uninstalled. An attacker could exploit this vulnerability by sending a stream of FCoE frames from an adjacent host to an affected device. An exploit could allow the attacker to cause packet amplification to occur, resulting in the saturation of interfaces and a DoS condition. Nexus 9000 Series Switches in Standalone NX-OS Mode are affected running software versions prior to 7.0(3)I7(5) and 9.2(2).

A vulnerability in the 802.1X implementation for 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 incomplete input validation of Extensible Authentication Protocol over LAN (EAPOL) frames. An attacker could exploit this vulnerability by sending a crafted EAPOL frame to an interface on the targeted device. A successful exploit could allow the attacker to cause the Layer 2 (L2) forwarding process to restart multiple times, leading to a system-level restart of the device and a DoS condition. Note: This vulnerability affects only NX-OS devices configured with 802.1X functionality. Cisco Nexus 1000V Switch for VMware vSphere devices are affected in versions prior to 5.2(1)SV3(1.4b). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(4). Nexus 3500 Platform Switches are affected in versions prior to 7.0(3)I7(4). Nexus 2000, 5500, 5600, and 6000 Series Switches are affected in versions prior to 7.3(5)N1(1) and 7.1(5)N1(1b). Nexus 7000 and 7700 Series Switches are affected in versions prior to 8.2(3). Nexus 9000 Series Fabric Switches in ACI Mode are affected in versions prior to 13.2(1l). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected in versions prior to 7.0(3)I7(4).

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 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 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 Control and Provisioning of Wireless Access Points (CAPWAP) protocol implementation of Cisco Aironet and Catalyst 9100 Access Points (APs) could allow an unauthenticated, adjacent attacker to cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to improper resource management during CAPWAP message processing. An attacker could exploit this vulnerability by sending a high volume of legitimate wireless management frames within a short time to an affected device. A successful exploit could allow the attacker to cause a device to restart unexpectedly, resulting in a DoS condition for clients associated with the AP.

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.

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 Open Shortest Path First (OSPF) implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) 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 improperly parses certain options in OSPF link-state advertisement (LSA) type 11 packets. An attacker could exploit this vulnerability by sending a crafted LSA type 11 OSPF packet to an affected device. A successful exploit could allow the attacker to cause a reload of the affected device, resulting in a DoS condition for client traffic that is traversing the 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.

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 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 IPv6 VPN over MPLS (6VPE) with Zone-Based Firewall (ZBFW) of 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 improper error handling of an IPv6 packet that is forwarded from an MPLS and ZBFW-enabled interface in a 6VPE deployment. An attacker could exploit this vulnerability by sending a crafted IPv6 packet sourced from a device on the IPv6-enabled virtual routing and forwarding (VRF) interface through the affected device. A successful exploit could allow the attacker to reload the device, resulting in a DoS condition.

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 implementation of Cisco Discovery Protocol functionality in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust memory on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper memory handling by the affected software when the software processes high rates of Cisco Discovery Protocol packets that are sent to a device. An attacker could exploit this vulnerability by sending a high rate of Cisco Discovery Protocol packets to an affected device. A successful exploit could allow the attacker to exhaust memory on the affected device, resulting in a DoS condition.

A vulnerability in 802.11 Wireless Multimedia Extensions (WME) action frame processing in Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to incomplete input validation of the 802.11 WME packet header. An attacker could exploit this vulnerability by sending malformed 802.11 WME frames to a targeted device. A successful exploit could allow the attacker to cause the WLC to reload unexpectedly. The fixed versions are 8.0.140.0, 8.2.130.0, and 8.3.111.0. Cisco Bug IDs: CSCva86353.

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.

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.

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 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 802.11r Fast Transition feature set of Cisco IOS 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 a corruption of certain timer mechanisms triggered by specific roaming events. This corruption will eventually cause a timer crash. An attacker could exploit this vulnerability by sending malicious reassociation events multiple times to the same AP in a short period of time, causing a DoS condition on the affected AP.

A vulnerability in the Cisco Discovery Protocol (CDP) module of Cisco IOS XE Software Releases 16.6.1 and 16.6.2 could allow an unauthenticated, adjacent attacker to cause a memory leak that may lead to a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain CDP packets. An attacker could exploit this vulnerability by sending certain CDP packets to an affected device. A successful exploit could cause an affected device to continuously consume memory and eventually result in a memory allocation failure that leads to a crash, triggering a reload of the affected device.

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 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 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 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.

A vulnerability in IPv6 traffic processing of Cisco IOS XE Wireless Controller Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a Layer 2 (L2) loop in a configured VLAN, resulting in a denial of service (DoS) condition for that VLAN. The vulnerability is due to a logic error when processing specific link-local IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet that would flow inbound through the wired interface of an affected device. A successful exploit could allow the attacker to cause traffic drops in the affected VLAN, thus triggering the 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 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.

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.