A vulnerability in the SSH service of Cisco Catalyst SD-WAN Manager could allow an unauthenticated, remote attacker to cause a process crash, resulting in a DoS condition for SSH access only. This vulnerability does not prevent the system from continuing to function, and web UI access is not affected. This vulnerability is due to insufficient resource management when an affected system is in an error condition. An attacker could exploit this vulnerability by sending malicious traffic to the affected system. A successful exploit could allow the attacker to cause the SSH process to crash and restart, resulting in a DoS condition for the SSH service.

Memory leak in the Cisco Tunneling Control Protocol (cTCP) encapsulation feature in Cisco IOS 12.4, when an Easy VPN (aka EZVPN) server is enabled, allows remote attackers to cause a denial of service (memory consumption and device crash) via a sequence of TCP packets.

Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for Mac, and Cisco Jabber for mobile platforms could allow an attacker to access sensitive information or cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

Cisco Unity 4.x before 4.2(1)ES161, 5.x before 5.0(1)ES53, and 7.x before 7.0(2)ES8, when using anonymous authentication (aka native Unity authentication), allows remote attackers to cause a denial of service (session exhaustion) via a large number of connections.

A vulnerability in the implementation of the IPv4 fragmentation reassembly code in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper management of resources during fragment reassembly. An attacker could exploit this vulnerability by sending specific sizes of fragmented packets to an affected device or through a Virtual Fragmentation Reassembly (VFR)-enabled interface on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Note: This vulnerability affects Cisco ASR 1000 Series Aggregation Services Routers and Cisco cBR-8 Converged Broadband Routers if they are running Cisco IOS XE Software Release 17.12.1 or 17.12.1a.

A vulnerability in the interaction between the TCP Intercept feature and the Snort 3 detection engine on Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured policies on an affected system. Devices that are configured with Snort 2 are not affected by this vulnerability. This vulnerability is due to a logic error when handling embryonic (half-open) TCP connections. An attacker could exploit this vulnerability by sending a crafted traffic pattern through an affected device. A successful exploit could allow unintended traffic to enter the network protected by the affected device.

A vulnerability in certain IPv4 fragment-processing functions of Cisco Remote PHY Software could allow an unauthenticated, remote attacker to impact traffic passing through a device, potentially causing a denial of service (DoS) condition. The vulnerability is due to the affected software not validating and calculating certain numerical values in IPv4 packets that are sent to an affected device. An attacker could exploit this vulnerability by sending malformed IPv4 traffic to an affected device. A successful exploit could allow the attacker to disrupt the flow of certain IPv4 traffic passing through an affected device, which could result in a DoS condition.

A vulnerability in the Rate Limiting Network Address Translation (NAT) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause high CPU utilization in the Cisco QuantumFlow Processor of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to mishandling of the rate limiting feature within the QuantumFlow Processor. An attacker could exploit this vulnerability by sending large amounts of traffic that would be subject to NAT and rate limiting through an affected device. A successful exploit could allow the attacker to cause the QuantumFlow Processor utilization to reach 100 percent on the affected device, resulting in a DoS condition.

A vulnerability in Address Resolution Protocol (ARP) management of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to prevent an affected device from resolving ARP entries for legitimate hosts on the connected subnets. This vulnerability exists because ARP entries are mismanaged. An attacker could exploit this vulnerability by continuously sending traffic that results in incomplete ARP entries. A successful exploit could allow the attacker to cause ARP requests on the device to be unsuccessful for legitimate hosts, resulting in a denial of service (DoS) condition.

Memory leak in Cisco Adaptive Security Appliances (ASA) 5500 Series and PIX Security Appliances 8.0 before 8.0(4) and 8.1 before 8.1(2) allows remote attackers to cause a denial of service (memory consumption) via an unspecified sequence of packets, related to the "initialization code for the hardware crypto accelerator."

Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for Mac, and Cisco Jabber for mobile platforms could allow an attacker to access sensitive information or cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the Simple Network Management Protocol (SNMP) punt handling function of Cisco cBR-8 Converged Broadband Routers could allow an authenticated, remote attacker to overload a device punt path, resulting in a denial of service (DoS) condition. This vulnerability is due to the punt path being overwhelmed by large quantities of SNMP requests. An attacker could exploit this vulnerability by sending a large number of SNMP requests to an affected device. A successful exploit could allow the attacker to overload the device punt path, resulting in a DoS condition.

A vulnerability in CLI management in Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to access the underlying operating system as the root user. This vulnerability is due to the way the software handles concurrent CLI sessions. An attacker could exploit this vulnerability by authenticating to the device as an administrative user and executing a sequence of commands. A successful exploit could allow the attacker to obtain access to the underlying operating system as the root user.

A vulnerability in the ingress traffic manager of Cisco IOS XE Software for Cisco Network Convergence System (NCS) 520 Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition in the web management interface of an affected device. This vulnerability is due to incorrect processing of certain IPv4 TCP traffic that is destined to an affected device. An attacker could exploit this vulnerability by sending a large number of crafted TCP packets to the affected device. A successful exploit could allow the attacker to cause the web management interface to become unavailable, resulting in a DoS condition. Note: This vulnerability does not impact traffic that is going through the device or going to the Management Ethernet interface of the device.

A vulnerability in Ethernet over GRE (EoGRE) packet processing of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9800 Family Wireless Controller, Embedded Wireless Controller, and Embedded Wireless on Catalyst 9000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper processing of malformed EoGRE packets. An attacker could exploit this vulnerability by sending malicious packets to the affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Cisco Secure ACS 3.x before 3.3(4) Build 12 patch 7, 4.0.x, 4.1.x before 4.1(4) Build 13 Patch 11, and 4.2.x before 4.2(0) Build 124 Patch 4 does not properly handle an EAP Response packet in which the value of the length field exceeds the actual packet length, which allows remote authenticated users to cause a denial of service (CSRadius and CSAuth service crash) or possibly execute arbitrary code via a crafted RADIUS (1) EAP-Response/Identity, (2) EAP-Response/MD5, or (3) EAP-Response/TLS Message Attribute packet.

Multiple vulnerabilities in the ingress packet processing function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Memory leak in the crypto functionality in Cisco Adaptive Security Appliance (ASA) 5500 devices 7.2 before 7.2(4)2, 8.0 before 8.0(3)14, and 8.1 before 8.1(1)4, when configured as a clientless SSL VPN endpoint, allows remote attackers to cause a denial of service (memory consumption and VPN hang) via a crafted SSL or HTTP packet, aka Bug ID CSCso66472.

A vulnerability in the web interface of Cisco Integrated Management Controller (IMC) Supervisor and Cisco UCS Director could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient restrictions on the size or total amount of resources allowed via the web interface. An attacker who has valid credentials for the application could exploit this vulnerability by sending a crafted or malformed HTTP request to the web interface. A successful exploit could allow the attacker to cause oversubscription of system resources or cause a component to become unresponsive, 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 the Cisco Webex Player for Webex Recording Format (WRF) files could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. An attacker could exploit this vulnerability by sending a user a link or email attachment with a malicious WRF file and persuading the user to open the file in the Cisco Webex Player. A successful exploit could cause the affected player to crash, resulting in a DoS condition. For more information about this vulnerability, see the Details section of this security advisory.

Cisco Adaptive Security Appliance (ASA) and Cisco PIX security appliance 7.2.x before 7.2(3)2 and 8.0.x before 8.0(2)17 allows remote attackers to cause a denial of service (device reload) via a port scan against TCP port 443 on the device.

A vulnerability in the TCP ingress handler for the data interfaces that are configured with management access to Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an increase in CPU and memory usage, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient ingress TCP rate limiting for TCP ports 22 (SSH) and 443 (HTTPS). An attacker could exploit this vulnerability by sending a crafted, steady stream of TCP traffic to port 22 or 443 on the data interfaces that are configured with management access to the affected device.

The virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (resource exhaustion) via a series of PPTP sessions, related to the persistence of interface descriptor block (IDB) data structures after process termination, aka bug ID CSCdv59309.

Memory leak in Cisco Content Switching Module (CSM) 4.2(3) up to 4.2(8) and Cisco Content Switching Module with SSL (CSM-S) 2.1(2) up to 2.1(7) allows remote attackers to cause a denial of service (memory consumption) via TCP segments with an unspecified combination of TCP flags.

Memory leak in the Certificate Trust List (CTL) Provider service in Cisco Unified Communications Manager (CUCM) 5.x before 5.1(3) allows remote attackers to cause a denial of service (memory consumption and service interruption) via a series of malformed TCP packets, as demonstrated by TCPFUZZ, aka Bug ID CSCsj80609.

Memory leak in the Certificate Trust List (CTL) Provider service in Cisco Unified Communications Manager (CUCM) 5.x before 5.1(3) and 6.x before 6.1(1) allows remote attackers to cause a denial of service (memory consumption and service interruption) via a series of malformed TCP packets, aka Bug ID CSCsi98433.

The data-link switching (DLSw) component in Cisco IOS 12.0 through 12.4 allows remote attackers to cause a denial of service (device restart or memory consumption) via crafted (1) UDP port 2067 or (2) IP protocol 91 packets.

Memory leak in the virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (memory consumption) via a series of PPTP sessions, related to "dead memory" that remains allocated after process termination, aka bug ID CSCsj58566.

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.

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.

Cisco Systems VPN Client IPSec Driver (CVPNDRVA.sys) 5.0.02.0090 allows local users to cause a denial of service (crash) by calling the 0x80002038 IOCTL with a small size value, which triggers memory corruption.

A vulnerability in the Secure Login Enhancements capability of Cisco Nexus 1000V Switch for VMware vSphere could allow an unauthenticated, remote attacker to cause an affected Nexus 1000V Virtual Supervisor Module (VSM) to become inaccessible to users through the CLI. The vulnerability is due to improper resource allocation during failed CLI login attempts when login parameters that are part of the Secure Login Enhancements capability are configured on an affected device. An attacker could exploit this vulnerability by performing a high amount of login attempts against the affected device. A successful exploit could cause the affected device to become inaccessible to other users, resulting in a denial of service (DoS) condition requiring a manual power cycle of the VSM to recover.

A vulnerability in the DHCP service of Cisco Industrial Network Director could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper handling of DHCP lease requests. An attacker could exploit this vulnerability by sending malicious DHCP lease requests to an affected application. A successful exploit could allow the attacker to cause the DHCP service to terminate, resulting in 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.

Cisco Unified Communications Manager (CUCM, formerly CallManager) 5.1 before 5.1(2), and Unified CallManager 5.0, allow remote attackers to cause a denial of service (kernel panic) via a flood of SIP INVITE messages to UDP port 5060, which triggers resource exhaustion, aka CSCsi75822.

A vulnerability in the FTP inspection engine of 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 exists because the affected software fails to release spinlocks when a device is running low on system memory, if the software is configured to apply FTP inspection and an access control rule to transit traffic, and the access control rule is associated with an FTP file policy. An attacker could exploit this vulnerability by sending a high rate of transit traffic through an affected device to cause a low-memory condition on the device. A successful exploit could allow the attacker to cause a software panic on the affected device, which could cause the device to reload and result in a temporary DoS condition.

A vulnerability in the Bulk Administration Tool (BAT) for Cisco Unity Connection could allow an authenticated, remote attacker to cause high disk utilization, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software does not restrict the maximum size of certain files that can be written to disk. An attacker who has valid administrator credentials for an affected system could exploit this vulnerability by sending a crafted, remote connection request to an affected system. A successful exploit could allow the attacker to write a file that consumes most of the available disk space on the system, causing application functions to operate abnormally and leading to a DoS condition.

Unspecified vulnerability in SSHield 1.6.1 with OpenSSH 3.0.2p1 on Cisco WebNS 8.20.0.1 on Cisco Content Services Switch (CSS) series 11000 devices allows remote attackers to cause a denial of service (connection slot exhaustion and device crash) via a series of large packets designed to exploit the SSH CRC32 attack detection overflow (CVE-2001-0144), possibly a related issue to CVE-2002-1024.

A vulnerability in the Shell Access Filter feature of Cisco Firepower Management Center (FMC), when used in conjunction with remote authentication, could allow an unauthenticated, remote attacker to cause high disk utilization, resulting in a denial of service (DoS) condition. The vulnerability occurs because the configuration of the Shell Access Filter, when used with a specific type of remote authentication, can cause a system file to have unbounded writes. An attacker could exploit this vulnerability by sending a steady stream of remote authentication requests to the appliance when the specific configuration is applied. Successful exploitation could allow the attacker to increase the size of a system log file so that it consumes most of the disk space. The lack of available disk space could lead to a DoS condition in which the device functions could operate abnormally, making the device unstable.

A vulnerability in the DNS input packet processor for Cisco Prime Network Registrar could allow an unauthenticated, remote attacker to cause the DNS process to momentarily restart, which could lead to a partial denial of service (DoS) condition on the affected system. The vulnerability is due to incomplete DNS packet header validation when the packet is received by the application. An attacker could exploit this vulnerability by sending a malformed DNS packet to the application. An exploit could allow the attacker to cause the DNS process to restart, which could lead to a DoS condition. This vulnerability affects Cisco Prime Network Registrar on all software versions prior to 8.3.5. Cisco Bug IDs: CSCvb55412.

A vulnerability in the detection engine parsing of Security Socket Layer (SSL) protocol packets for Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to the Snort process unexpectedly restarting. The vulnerability is due to improper input handling of the SSL traffic. An attacker could exploit this vulnerability by sending a crafted SSL traffic to the detection engine on the targeted device. An exploit could allow the attacker to cause a DoS condition if the Snort process restarts and traffic inspection is bypassed or traffic is dropped. Cisco Bug IDs: CSCvi36434.

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 Cisco AMP for Endpoints Mac Connector Software installed on Apple macOS 10.12 could allow an unauthenticated, remote attacker to cause a kernel panic on an affected system, resulting in a denial of service (DoS) condition. The vulnerability exists if the affected software is running in Block network conviction mode. Exploitation could occur if the system that is running the affected software starts a server process and an address in the IP blacklist cache of the affected software attempts to connect to the affected system. 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. Cisco Bug IDs: CSCvk08192.

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 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 Session Initiation Protocol (SIP) call-handling functionality of Cisco IP Phone 6800, 7800, and 8800 Series Phones with Multiplatform Firmware could allow an unauthenticated, remote attacker to cause an affected phone to reload unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability exists because the firmware of an affected phone incorrectly handles errors that could occur when an incoming phone call is not answered. An attacker could exploit this vulnerability by sending a set of maliciously crafted SIP packets to an affected phone. A successful exploit could allow the attacker to cause the affected phone to reload unexpectedly, resulting in a temporary DoS condition. This vulnerability affects Cisco IP Phone 6800, 7800, and 8800 Series Phones with Multiplatform Firmware if they are running a Multiplatform Firmware release prior to Release 11.1(2). Cisco Bug IDs: CSCvi24718.

A vulnerability in TCP connection management in Cisco Prime Access Registrar could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition when the application unexpectedly restarts. The vulnerability is due to incorrect handling of incoming TCP SYN packets to specific listening ports. The improper handling of the TCP SYN packets could cause a system file description to be allocated and not freed. An attacker could exploit this vulnerability by sending a crafted stream of TCP SYN packets to the application. A successful exploit could allow the attacker to cause the application to eventually restart if a file description cannot be obtained.

A vulnerability in the IPsec Manager of Cisco StarOS for Cisco Aggregation Services Router (ASR) 5000 Series Routers and Virtualized Packet Core (VPC) System Software could allow an unauthenticated, remote attacker to terminate all active IPsec VPN tunnels and prevent new tunnels from being established, resulting in a denial of service (DoS) condition. The vulnerability is due to improper processing of corrupted Internet Key Exchange Version 2 (IKEv2) messages. An attacker could exploit this vulnerability by sending crafted IKEv2 messages toward an affected router. A successful exploit could allow the attacker to cause the ipsecmgr service to reload. A reload of this service could cause all IPsec VPN tunnels to be terminated and prevent new tunnels from being established until the service has restarted, resulting in a DoS condition. This vulnerability affects the following Cisco products when they are running Cisco StarOS: Cisco Aggregation Services Router (ASR) 5000 Series Routers, Virtualized Packet Core (VPC) System Software. Cisco Bug IDs: CSCve29605.

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the affected software insufficiently validates Cisco Fabric Services packets when the software processes packet data. An attacker could exploit this vulnerability by sending a maliciously crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to cause a buffer overflow condition on the device, which could cause process crashes and result in a DoS condition on the device. This vulnerability affects Firepower 4100 Series Next-Generation Firewalls, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 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 standalone 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: CSCvd69960, CSCve02463, CSCve04859, CSCve41530, CSCve41537, CSCve41541, CSCve41557.