A vulnerability in the WLAN Local Profiling feature of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect parsing of HTTP packets while performing HTTP-based endpoint device classifications. An attacker could exploit this vulnerability by sending a crafted HTTP packet to an affected device. A successful exploit could cause an affected device to reboot, resulting in a DoS condition.

A vulnerability in the IP fragment-handling implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak on an affected device. This memory leak could prevent traffic from being processed through the device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper error handling when specific failures occur during IP fragment reassembly. An attacker could exploit this vulnerability by sending crafted, fragmented IP traffic to a targeted device. A successful exploit could allow the attacker to continuously consume memory on the affected device and eventually impact traffic, resulting in a DoS condition. The device could require a manual reboot to recover from the DoS condition. Note: This vulnerability applies to both IP Version 4 (IPv4) and IP Version 6 (IPv6) traffic.

A vulnerability in the Cisco Discovery Protocol of Cisco Video Surveillance 8000 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. The vulnerability is due to incorrect processing of certain Cisco Discovery Protocol packets. An attacker could exploit this vulnerability by sending certain Cisco Discovery Protocol 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 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 resource handling system of Cisco NX-OS Software for Cisco MDS 9000 Series Multilayer Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource usage control. An attacker could exploit this vulnerability by sending traffic to the management interface (mgmt0) of an affected device at very high rates. An exploit could allow the attacker to cause unexpected behaviors such as high CPU usage, process crashes, or even full system reboots of an affected device.

A vulnerability in the locally significant certificate (LSC) provisioning feature of Cisco Catalyst 9800 Series Wireless Controllers that are running Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a memory leak that could lead to a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain public key infrastructure (PKI) packets. An attacker could exploit this vulnerability by sending crafted Secure Sockets Layer (SSL) packets to an affected device. A successful exploit could cause an affected device to continuously consume memory, which could result in a memory allocation failure that leads to a crash and causes a DoS condition.

A vulnerability in Cisco SD-WAN Solution Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper validation of fields in Cisco SD-WAN peering messages that are encapsulated in UDP packets. An attacker could exploit this vulnerability by sending crafted UDP messages to the targeted system. A successful exploit could allow the attacker to cause services on the device to fail, resulting in a DoS condition that could impact the targeted device and other devices that depend on it.

A vulnerability in the Link Layer Discovery Protocol (LLDP) feature of Cisco Webex Room Phone and Cisco Webex Share devices could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient resource allocation. An attacker could exploit this vulnerability by sending crafted LLDP traffic to an affected device. A successful exploit could allow the attacker to exhaust the memory resources of the affected device, resulting in a crash of the LLDP process. If the affected device is configured to support LLDP only, this could cause an interruption to inbound and outbound calling. By default, these devices are configured to support both Cisco Discovery Protocol and LLDP. To recover operational state, the affected device needs a manual restart.

A vulnerability in the OSPF Version 2 (OSPFv2) implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to incomplete input validation when the affected software processes certain OSPFv2 packets with Link-Local Signaling (LLS) data. An attacker could exploit this vulnerability by sending a malformed OSPFv2 packet to an affected device. A successful exploit could allow the attacker to cause an affected device to reload, resulting in a DoS condition.

A vulnerability in the IP Address Resolution Protocol (ARP) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation Services Routers with a 20-Gbps Embedded Services Processor (ESP) installed could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service condition. The vulnerability is due to insufficient error handling when an affected device has reached platform limitations. An attacker could exploit this vulnerability by sending a malicious series of IP ARP messages to an affected device. A successful exploit could allow the attacker to exhaust system resources, which would eventually cause the affected device to reload.

A vulnerability in the local management (local-mgmt) CLI of Cisco UCS Manager Software could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of CLI command parameters. An attacker could exploit this vulnerability by executing specific commands on the local-mgmt CLI on an affected device. A successful exploit could allow the attacker to cause internal system processes to fail to terminate properly, which could result in a buildup of stuck processes and lead to slowness in accessing the UCS Manager CLI and web UI. A sustained attack may result in a restart of internal UCS Manager processes and a temporary loss of access to the UCS Manager CLI and web UI.

A vulnerability in Cisco Aironet Access Point (AP) Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper handling of clients that are trying to connect to the AP. An attacker could exploit this vulnerability by sending authentication requests from multiple clients to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.

A vulnerability in the Internet Key Exchange version 1 (IKEv1) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper management of system memory. An attacker could exploit this vulnerability by sending malicious IKEv1 traffic to an affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

A vulnerability in the Polaris kernel of Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to crash the device. The vulnerability is due to insufficient packet size validation. An attacker could exploit this vulnerability by sending jumbo frames or frames larger than the configured MTU size to the management interface of this device. A successful exploit could allow the attacker to crash the device fully before an automatic recovery.

A vulnerability in the SSL/TLS session handler of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a memory leak when closing SSL/TLS connections in a specific state. An attacker could exploit this vulnerability by establishing several SSL/TLS sessions and ensuring they are closed under certain conditions. A successful exploit could allow the attacker to exhaust memory resources in the affected device, which would prevent it from processing new SSL/TLS connections, resulting in a DoS. Manual intervention is required to recover an affected device.

A vulnerability in the ICMP ingress packet processing of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 4110 appliances could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to incomplete input validation upon receiving ICMP packets. An attacker could exploit this vulnerability by sending a high number of crafted ICMP or ICMPv6 packets to an affected device. A successful exploit could allow the attacker to cause a memory exhaustion condition that may result in an unexpected reload. No manual intervention is needed to recover the device after the reload.

A vulnerability in the Open Shortest Path First (OSPF) implementation in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak on an affected device. The vulnerability is due to incorrect processing of certain OSPF packets. An attacker could exploit this vulnerability by sending a series of crafted OSPF packets to be processed by an affected device. A successful exploit could allow the attacker to continuously consume memory on an affected device and eventually cause it to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the IPsec packet processor of Cisco IOS XR Software could allow an unauthenticated remote attacker to cause a denial of service (DoS) condition for IPsec sessions to an affected device. The vulnerability is due to improper handling of packets by the IPsec packet processor. An attacker could exploit this vulnerability by sending malicious ICMP error messages to an affected device that get punted to the IPsec packet processor. A successful exploit could allow the attacker to deplete IPsec memory, resulting in all future IPsec packets to an affected device being dropped by the device. Manual intervention is required to recover from this situation.

A vulnerability in the licensing service of Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.The vulnerability is due to improper handling of system resource values by the affected system. An attacker could exploit this vulnerability by sending malicious requests to the targeted system. A successful exploit could allow the attacker to cause the affected system to become unresponsive, resulting in a DoS condition and preventing the management of dependent devices.

A vulnerability in the ARP packet processing of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Security Appliances could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect processing of ARP packets received by the management interface of an affected device. An attacker could exploit this vulnerability by sending a series of unicast ARP packets in a short timeframe that would reach the management interface of an affected device. A successful exploit could allow the attacker to consume resources on an affected device, which would prevent the device from sending internal system keepalives and eventually cause the device to reload, resulting in a denial of service (DoS) condition.

Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to either immediately crash the Internet Group Management Protocol (IGMP) process or make it consume available memory and eventually crash. The memory consumption may negatively impact other processes that are running on the device. These vulnerabilities are due to the incorrect handling of IGMP packets. An attacker could exploit these vulnerabilities by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to immediately crash the IGMP process or cause memory exhaustion, resulting in other processes becoming unstable. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address these vulnerabilities.

A vulnerability in the PROFINET handler for Link Layer Discovery Protocol (LLDP) messages of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a crash on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of LLDP messages in the PROFINET LLDP message handler. An attacker could exploit this vulnerability by sending a malicious LLDP message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.

A vulnerability in Cisco Aironet Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) on an affected device. The vulnerability is due to improper resource management while processing specific packets. An attacker could exploit this vulnerability by sending a series of crafted UDP packets to a specific port on an affected device. A successful exploit could either allow the attacker to tear down the connection between the AP and the wireless LAN controller, resulting in the affected device not being able to process client traffic, or cause the vulnerable device to reload, triggering a DoS condition. After the attack, the affected device should automatically recover its normal functions without manual intervention.

A vulnerability in the DNS functionality of Cisco Nexus Dashboard Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to the improper processing of DNS requests. An attacker could exploit this vulnerability by sending a continuous stream of DNS requests to an affected device. A successful exploit could allow the attacker to cause the coredns service to stop working or cause the device to reload, resulting in a DoS condition.

A vulnerability in the Umbrella Connector component of Cisco IOS XE Software for Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to trigger a reload, resulting in a denial of service condition on an affected device. The vulnerability is due to insufficient error handling when parsing DNS requests. An attacker could exploit this vulnerability by sending a series of malicious DNS requests to an Umbrella Connector client interface of an affected device. A successful exploit could allow the attacker to cause a crash of the iosd process, which triggers a reload of the affected device.

A vulnerability in the packet processing functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to inefficient memory management. An attacker could exploit this vulnerability by sending a large number of TCP packets to a specific port on an affected device. A successful exploit could allow the attacker to exhaust system memory, which could cause the device to reload unexpectedly. No manual intervention is needed to recover the device after it has reloaded.

A vulnerability in the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) handler of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust memory resources on the affected device, leading to a denial of service (DoS) condition. The vulnerability is due to improper resource management for inbound SSL/TLS connections. An attacker could exploit this vulnerability by establishing multiple SSL/TLS connections with specific conditions to the affected device. A successful exploit could allow the attacker to exhaust the memory on the affected device, causing the device to stop accepting new SSL/TLS connections and resulting in a DoS condition for services on the device that process SSL/TLS traffic. Manual intervention is required to recover an affected device.

A vulnerability in the Cisco Discovery Protocol of Cisco Video Surveillance 8000 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. The vulnerability is due to incorrect processing of certain Cisco Discovery Protocol packets. An attacker could exploit this vulnerability by sending certain Cisco Discovery Protocol 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 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 implementation of Multiprotocol Border Gateway Protocol (MP-BGP) for the Layer 2 VPN (L2VPN) Ethernet VPN (EVPN) address family in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of Border Gateway Protocol (BGP) update messages that contain crafted EVPN attributes. An attacker could exploit this vulnerability by sending BGP update messages with specific, malformed attributes to an affected device. A successful exploit could allow the attacker to cause an affected device to crash, resulting in a DoS condition.

A vulnerability in the VPN System Logging functionality for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak that can deplete system memory over time, which can cause unexpected system behaviors or device crashes. The vulnerability is due to the system memory not being properly freed for a VPN System Logging event generated when a VPN session is created or deleted. An attacker could exploit this vulnerability by repeatedly creating or deleting a VPN tunnel connection, which could leak a small amount of system memory for each logging event. A successful exploit could allow the attacker to cause system memory depletion, which can lead to a systemwide denial of service (DoS) condition. The attacker does not have any control of whether VPN System Logging is configured or not on the device, but it is enabled by default.

A vulnerability in the PROFINET feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause an affected device to crash and reload, resulting in a denial of service (DoS) condition on the device. The vulnerability is due to insufficient processing logic for crafted PROFINET packets that are sent to an affected device. An attacker could exploit this vulnerability by sending crafted PROFINET packets to an affected device for processing. A successful exploit could allow the attacker to cause the device to crash and reload, resulting in a DoS condition on the device.

A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to exhaust process memory of an affected device. The vulnerability is due to insufficient queue management for Internet Group Management Protocol (IGMP) packets. An attacker could exploit this vulnerability by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to cause memory exhaustion, resulting in instability of other processes. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address this vulnerability.

A vulnerability in the web interface of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. An exploit could allow the attacker to cause a DoS condition. Note: This vulnerability applies to IP Version 4 (IPv4) and IP Version 6 (IPv6) HTTP traffic.

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 SSL VPN negotiation process for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to inefficient direct memory access (DMA) memory management during the negotiation phase of an SSL VPN connection. An attacker could exploit this vulnerability by sending a steady stream of crafted Datagram TLS (DTLS) traffic to an affected device. A successful exploit could allow the attacker to exhaust DMA memory on the device and cause a DoS condition.

A vulnerability in Cisco Aironet Series Access Points Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to the improper processing of client packets that are sent to an affected access point (AP). An attacker could exploit this vulnerability by sending a large number of sustained client packets to the affected AP. A successful exploit could allow the attacker to cause the affected AP to crash, resulting in a DoS condition.

A vulnerability in Cisco 900 Series Aggregation Services Router (ASR) software could allow an unauthenticated, remote attacker to cause a partial denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient handling of certain broadcast packets ingress to the device. An attacker could exploit this vulnerability by sending large streams of broadcast packets to an affected device. If successful, an exploit could allow an attacker to impact services running on the device, resulting in a partial DoS condition.

Cisco IOS 12.2(15) and earlier allows remote attackers to cause a denial of service (refused VTY (virtual terminal) connections), via a crafted TCP connection to the Telnet or reverse Telnet port.

The SSL VPN implementation in Cisco Adaptive Security Appliance (ASA) Software 9.3(.2) and earlier does not properly allocate memory blocks during HTTP packet handling, which allows remote attackers to cause a denial of service (memory consumption) via crafted packets, aka Bug ID CSCuq68888.

The Intercluster Sync Agent Service in Cisco Unified Presence Server allows remote attackers to cause a denial of service via a TCP SYN flood, aka Bug ID CSCun34125.

A vulnerability in the application server of the Cisco Unified Customer Voice Portal (CVP) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability is due to malformed SIP INVITE traffic received on the CVP during communications with the Cisco Virtualized Voice Browser (VVB). An attacker could exploit this vulnerability by sending malformed SIP INVITE traffic to the targeted appliance. An exploit could allow the attacker to impact the availability of services and data on the device, causing a DoS condition. This vulnerability affects Cisco Unified CVP running any software release prior to 11.6(1). Cisco Bug IDs: CSCve85840.

A vulnerability in the Cisco IOx Application Framework of Cisco 809 Industrial Integrated Services Routers (Industrial ISRs), Cisco 829 Industrial ISRs, Cisco CGR 1000 Compute Module, and Cisco IC3000 Industrial Compute Gateway could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling during packet processing. An attacker could exploit this vulnerability by sending a high and sustained rate of crafted TCP traffic to the IOx web server on an affected device. A successful exploit could allow the attacker to cause the IOx web server to stop processing requests, resulting in a DoS condition.

Attackers can crash a Cisco IOS router or device, provided they can get to an interactive prompt (such as a login). This applies to some IOS 9.x, 10.x, and 11.x releases.

A vulnerability in the Layer 2 Tunneling Protocol (L2TP) parsing function of Cisco IOS (12.0 through 12.4 and 15.0 through 15.6) and Cisco IOS XE (3.1 through 3.18) could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to insufficient validation of L2TP packets. An attacker could exploit this vulnerability by sending a crafted L2TP packet 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. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS or Cisco IOS XE Software if the L2TP feature is enabled for the device and the device is configured as an L2TP Version 2 (L2TPv2) or L2TP Version 3 (L2TPv3) endpoint. By default, the L2TP feature is not enabled. Cisco Bug IDs: CSCuy82078.