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 VLAN Trunking Protocol (VTP) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to corrupt the internal VTP database on an affected device and cause a denial of service (DoS) condition. The vulnerability is due to a logic error in how the affected software handles a subset of VTP packets. An attacker could exploit this vulnerability by sending VTP packets in a sequence that triggers a timeout in the VTP message processing code of the affected software. A successful exploit could allow the attacker to impact the ability to create, modify, or delete VLANs and cause a DoS condition. There are workarounds that address this vulnerability. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS Software or Cisco IOS XE Software, are operating in VTP client mode or VTP server mode, and do not have a VTP domain name configured. The default configuration for Cisco devices that are running Cisco IOS Software or Cisco IOS XE Software and support VTP is to operate in VTP server mode with no domain name configured.

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 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 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.

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 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.

Multiple vulnerabilities in the implementation of the Cisco Discovery Protocol and Link Layer Discovery Protocol (LLDP) for Cisco Video Surveillance 7000 Series IP Cameras could allow an unauthenticated, adjacent attacker to cause a memory leak, which could lead to a denial of service (DoS) condition on an affected device. These vulnerabilities are due to incorrect processing of certain Cisco Discovery Protocol and LLDP packets at ingress time. An attacker could exploit these vulnerabilities by sending crafted Cisco Discovery Protocol or LLDP packets to an affected device. A successful exploit could allow the attacker to cause the affected device to continuously consume memory, which could cause the device to crash and reload, resulting in a DoS condition. Note: Cisco Discovery Protocol and LLDP are Layer 2 protocols. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

Multiple vulnerabilities exist in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business RV Series Routers. An unauthenticated, adjacent attacker could execute arbitrary code or cause an affected router to leak system memory or reload. A memory leak or device reload would cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory. 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 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 deep packet inspection (DPI) engine of Cisco SD-WAN vEdge Routers could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient handling of malformed packets. An attacker could exploit this vulnerability by sending crafted packets through an affected device. A successful exploit could allow the attacker to cause the device to reboot, resulting in a DoS condition.

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.