A vulnerability in the TCP connection handling functionality of Cisco Remote Expert Manager Software 11.0.0 could allow an unauthenticated, remote attacker to disable TCP ports and cause a denial of service (DoS) condition on an affected system. The vulnerability is due to a lack of rate-limiting functionality in the TCP Listen application of the affected software. An attacker could exploit this vulnerability by sending a crafted TCP traffic stream in which specific types of TCP packets are flooded to an affected device, for example a TCP packet stream in which the TCP FIN bit is set in all the TCP packets. A successful exploit could allow the attacker to cause certain TCP listening ports on the affected system to stop accepting incoming connections for a period of time or until the affected device is restarted, resulting in a DoS condition. In addition, system resources, such as CPU and memory, could be exhausted during the attack. Cisco Bug IDs: CSCva29806.

A vulnerability in the HTTP remote procedure call (RPC) service of set-top box (STB) receivers manufactured by Cisco for Yes could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the firmware of an affected device fails to handle certain XML values that are passed to the HTTP RPC service listening on the local subnet of the device. An attacker could exploit this vulnerability by submitting a malformed request to an affected device. A successful attack could cause the affected device to restart, resulting in a DoS condition. Yes has updated the affected devices with firmware that addresses this vulnerability. Customers are not required to take action. Vulnerable Products: This vulnerability affects YesMaxTotal, YesMax HD, and YesQuattro STB devices. Cisco Bug IDs: CSCvd08812.

A vulnerability in the ingress UDP packet processing functionality of Cisco Virtualized Packet Core-Distributed Instance (VPC-DI) Software 19.2 through 21.0 could allow an unauthenticated, remote attacker to cause both control function (CF) instances on an affected system to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient handling of user-supplied data by the affected software. An attacker could exploit this vulnerability by sending crafted UDP packets to the distributed instance (DI) network addresses of both CF instances on an affected system. A successful exploit could allow the attacker to cause an unhandled error condition on the affected system, which would cause the CF instances to reload and consequently cause the entire VPC to reload, resulting in the disconnection of all subscribers and a DoS condition on the affected system. This vulnerability can be exploited via IPv4 traffic only. Cisco Bug IDs: CSCvc01665 CSCvc35565.

A vulnerability in the logging configuration of Secure Sockets Layer (SSL) policies for Cisco FirePOWER System Software 5.3.0 through 6.2.2 could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to high consumption of system resources. The vulnerability is due to the logging of certain TCP packets by the affected software. An attacker could exploit this vulnerability by sending a flood of crafted TCP packets to an affected device. A successful exploit could allow the attacker to cause a DoS condition. The success of an exploit is dependent on how an administrator has configured logging for SSL policies for a device. This vulnerability affects Cisco FirePOWER System Software that is configured to log connections by using SSL policy default actions. Cisco Bug IDs: CSCvd07072.

A vulnerability in the TCP throttling process for the GUI of the Cisco Identity Services Engine (ISE) 2.1(0.474) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device where the ISE GUI may fail to respond to new or established connection requests. The vulnerability is due to insufficient TCP rate limiting protection on the GUI. An attacker could exploit this vulnerability by sending the affected device a high rate of TCP connections to the GUI. An exploit could allow the attacker to cause the GUI to stop responding while the high rate of connections is in progress. Cisco Bug IDs: CSCvc81803.

Multiple Cisco products are affected by a vulnerability in local file management for certain system log files of Cisco collaboration products that could allow an unauthenticated, remote attacker to cause high disk utilization, resulting in a denial of service (DoS) condition. The vulnerability occurs because a certain system log file does not have a maximum size restriction. Therefore, the file is allowed to consume the majority of available disk space on the appliance. An attacker could exploit this vulnerability by sending crafted remote connection requests to the appliance. 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 application functions could operate abnormally, making the appliance unstable. This vulnerability affects the following Cisco Voice Operating System (VOS)-based products: Emergency Responder, Finesse, Hosted Collaboration Mediation Fulfillment, MediaSense, Prime License Manager, SocialMiner, Unified Communications Manager (UCM), Unified Communications Manager IM and Presence Service (IM&P - earlier releases were known as Cisco Unified Presence), Unified Communication Manager Session Management Edition (SME), Unified Contact Center Express (UCCx), Unified Intelligence Center (UIC), Unity Connection, Virtualized Voice Browser. This vulnerability also affects Prime Collaboration Assurance and Prime Collaboration Provisioning. Cisco Bug IDs: CSCvd10872, CSCvf64322, CSCvf64332, CSCvi29538, CSCvi29543, CSCvi29544, CSCvi29546, CSCvi29556, CSCvi29571, CSCvi31738, CSCvi31741, CSCvi31762, CSCvi31807, CSCvi31818, CSCvi31823.

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 web user interface of Cisco IOS XE 3.1 through 3.17 could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to insufficient resource handling by the affected software when the web user interface is under a high load. An attacker could exploit this vulnerability by sending a high number of requests to the web user interface of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. To exploit this vulnerability, the attacker must have access to the management interface of the affected software, which is typically connected to a restricted management network. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS XE Software, if the web user interface of the software is enabled. By default, the web user interface is not enabled. Cisco Bug IDs: CSCup70353.

A vulnerability in the Stream Control Transmission Protocol (SCTP) decoder of the Cisco NetFlow Generation Appliance (NGA) with software before 1.1(1a) could allow an unauthenticated, remote attacker to cause the device to hang or unexpectedly reload, causing a denial of service (DoS) condition. The vulnerability is due to incomplete validation of SCTP packets being monitored on the NGA data ports. An attacker could exploit this vulnerability by sending malformed SCTP packets on a network that is monitored by an NGA data port. SCTP packets addressed to the IP address of the NGA itself will not trigger this vulnerability. An exploit could allow the attacker to cause the appliance to become unresponsive or reload, causing a DoS condition. User interaction could be needed to recover the device using the reboot command from the CLI. The following Cisco NetFlow Generation Appliances are vulnerable: NGA 3140, NGA 3240, NGA 3340. Cisco Bug IDs: CSCvc83320.

Multiple vulnerabilities in the Server Message Block (SMB) Protocol preprocessor detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, adjacent or remote attacker to cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.

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.

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 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.

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 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 management interface access control list (ACL) configuration of Cisco NX-OS System Software could allow an unauthenticated, remote attacker to bypass configured ACLs on the management interface. This could allow traffic to be forwarded to the NX-OS CPU for processing, leading to high CPU utilization and a denial of service (DoS) condition. The vulnerability is due to a bad code fix in the 7.3.2 code train that could allow traffic to the management interface to be misclassified and not match the proper configured ACLs. An attacker could exploit this vulnerability by sending crafted traffic to the management interface. An exploit could allow the attacker to bypass the configured management interface ACLs and impact the CPU of the targeted device, resulting in a DoS condition. This vulnerability affects the following Cisco products running Cisco NX-OS System Software: Multilayer Director Switches, Nexus 2000 Series Switches, Nexus 3000 Series 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. Cisco Bug IDs: CSCvf31132.

A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol component of Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper input validation on fields within CAPWAP Discovery Request packets by the affected device. An attacker could exploit this vulnerability by sending malicious CAPWAP Discovery Request packets to the Cisco WLC Software. A successful exploit could allow the attacker to cause the Cisco WLC Software to disconnect associated access points (APs). While the APs disconnect and reconnect, service will be unavailable for a brief period of time, resulting in a DoS condition.

A vulnerability in IPv6 ingress packet processing for Cisco UCS Central Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to high CPU utilization on the targeted device. The vulnerability is due to insufficient rate limiting protection for IPv6 ingress traffic. An attacker could exploit this vulnerability by sending the affected device a high rate of IPv6 packets. Successful exploitation could allow the attacker to cause a DoS condition due to CPU and resource constraints. Cisco Bug IDs: CSCuv34544.

A vulnerability in the TCP throttling process of Cisco Prime Network could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient rate limiting protection for TCP listening ports. An attacker could exploit this vulnerability by sending the affected device a high rate of TCP SYN packets to the local IP address of the targeted application. A successful exploit could allow the attacker to cause the device to consume a high amount of memory and become slow, or to stop accepting new TCP connections to the application. Cisco Bug IDs: CSCvg48152.

A vulnerability in the detection engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause one of the detection engine processes to run out of memory and thus slow down traffic processing. The vulnerability is due to improper handling of traffic when the Secure Sockets Layer (SSL) inspection policy is enabled. An attacker could exploit this vulnerability by sending malicious traffic through an affected device. An exploit could allow the attacker to increase the resource consumption of a single instance of the Snort detection engine on an affected device. This will lead to performance degradation and eventually the restart of the affected Snort process. Cisco Bug IDs: CSCvi09219, CSCvi29845.

A vulnerability in the Precision Time Protocol (PTP) subsystem of Cisco IOS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition of the Precision Time Protocol. The vulnerability is due to insufficient processing of PTP packets. An attacker could exploit this vulnerability by sending a custom PTP packet to, or through, an affected device. A successful exploit could allow the attacker to cause a DoS condition for the PTP subsystem, resulting in time synchronization issues across the network.

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 Session Initiation Protocol (SIP) of the Cisco TelePresence Codec (TC) and Collaboration Endpoint (CE) Software could allow an unauthenticated, remote attacker to cause a TelePresence endpoint to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of flow-control mechanisms within the software. An attacker could exploit this vulnerability by sending a flood of SIP INVITE packets to the affected device. An exploit could allow the attacker to impact the availability of services and data of the device, including a complete DoS condition. This vulnerability affects the following Cisco TC and CE platforms when running software versions prior to TC 7.3.8 and CE 8.3.0. Cisco Bug IDs: CSCux94002.

A vulnerability in the TCP throttling process for Cisco IoT Field Network Director (IoT-FND) could allow an unauthenticated, remote attacker to cause the system to consume additional memory, eventually forcing the device to restart, aka Memory Exhaustion. The vulnerability is due to insufficient rate-limiting protection. An attacker could exploit this vulnerability by sending a high rate of TCP packets to a specific group of open listening ports on a targeted device. An exploit could allow the attacker to cause the system to consume additional memory. If enough available memory is consumed, the system will restart, creating a temporary denial of service (DoS) condition. The DoS condition will end after the device has finished the restart process. This vulnerability affects the following Cisco products: Connected Grid Network Management System, if running a software release prior to IoT-FND Release 4.0; IoT Field Network Director, if running a software release prior to IoT-FND Release 4.0. Cisco Bug IDs: CSCvc77164.

A vulnerability in the Session Initiation Protocol (SIP) UDP throttling process of Cisco Unified Communications Manager (Cisco Unified CM) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient rate limiting protection. An attacker could exploit this vulnerability by sending the affected device a high rate of SIP messages. An exploit could allow the attacker to cause the device to reload unexpectedly. The device and services will restart automatically. This vulnerability affects Cisco Unified Communications Manager (CallManager) releases prior to the first fixed release; the following list indicates the first minor release that includes the fix for this vulnerability: 10.5.2.14900-16 11.0.1.23900-5 11.5.1.12900-2. Cisco Bug IDs: CSCuz72455.

IP-in-IP protocol specifies IP Encapsulation within IP standard (RFC 2003, STD 1) that decapsulate and route IP-in-IP traffic is vulnerable to spoofing, access-control bypass and other unexpected behavior due to the lack of validation to verify network packets before decapsulation and routing.

Cisco ONS 15216 Optical Add/Drop Multiplexer (OADM) running firmware 2.2.2 and earlier allows remote attackers to cause a denial of service (management plane session loss) via crafted telnet data.

The traffic engineering (TE) processing subsystem in Cisco IOS XR allows remote attackers to cause a denial of service (process restart) via crafted TE packets, aka Bug ID CSCue04000.

The Control and Provisioning of Wireless Access Points (CAPWAP) protocol implementation on Cisco Wireless LAN Controller (WLC) devices allows remote attackers to cause a denial of service via a crafted CAPWAP packet that triggers a buffer over-read, aka Bug ID CSCuh81880.

The tNetTaskLimit process on the Transport Node Controller (TNC) on Cisco ONS 15454 devices with software 9.6 and earlier does not properly prioritize health pings, which allows remote attackers to cause a denial of service (watchdog timeout and TNC reset) via a flood of network traffic, aka Bug ID CSCud97155.

The SNMP module in Cisco IOS XR allows remote attackers to cause a denial of service (process reload) via a request for an unspecified MIB, aka Bug ID CSCuh43144.

Cisco Identity Services Engine does not properly restrict the creation of guest accounts, which allows remote attackers to cause a denial of service (exhaustion of the account supply) via a series of requests within one session, aka Bug ID CSCue94287.

Buffer overflow in the web-application interface on Cisco 9900 IP phones allows remote attackers to cause a denial of service (webapp interface outage) via long values in unspecified fields, aka Bug ID CSCuh10343.

The PPTP-ALG component in CRS Carrier Grade Services Engine (CGSE) and ASR 9000 Integrated Service Module (ISM) in Cisco IOS XR allows remote attackers to cause a denial of service (module reset) via crafted packet streams, aka Bug ID CSCue91963.

The Java process in the Impact server in Cisco Prime Central for Hosted Collaboration Solution (HCS) allows remote attackers to cause a denial of service (process crash) via a flood of TCP packets, aka Bug ID CSCug57345.

Cisco Secure Access Control System (ACS) does not properly implement an incoming-packet firewall rule, which allows remote attackers to cause a denial of service (process crash) via a flood of crafted packets, aka Bug ID CSCui51521.

Cisco Secure Access Control System (ACS) does not properly handle requests to read from the TACACS+ socket, which allows remote attackers to cause a denial of service (process crash) via malformed TCP packets, aka Bug ID CSCuh12488.

A vulnerability in the web UI of Cisco Umbrella could allow an unauthenticated, remote attacker to negatively affect the performance of this service. The vulnerability exists due to insufficient rate limiting controls in the web UI. An attacker could exploit this vulnerability by sending crafted HTTPS packets at a high and sustained rate. A successful exploit could allow the attacker to negatively affect the performance of the web UI. Cisco has addressed this vulnerability.

The Precision Video Engine component in Cisco Jabber for Windows and Cisco Virtualization Experience Media Engine allows remote attackers to cause a denial of service (process crash and call disconnection) via crafted RTP packets, aka Bug IDs CSCuh60706 and CSCue21117.

The RIP process in Cisco IOS XR allows remote attackers to cause a denial of service (process crash) via a crafted version-2 RIP packet, aka Bug ID CSCue46731.

Cisco Hosted Collaboration Mediation allows remote attackers to cause a denial of service (CPU consumption) via a flood of malformed UDP packets on port 162, aka Bug ID CSCug85756.

The Connection Manager in Cisco Jabber Extensible Communications Platform (aka Jabber XCP) does not properly validate login data, which allows remote attackers to cause a denial of service (service crash) by sending a series of malformed login packets, aka Bug ID CSCts76762.

Cisco NX-OS on the Nexus 1000V does not assign the proper priority to heartbeat messages from a Virtual Ethernet Module (VEM) to a Virtual Supervisor Module (VSM), which allows remote attackers to cause a denial of service (false VEM unavailability report) via a flood of UDP packets, aka Bug ID CSCud14840.

The C-Series Rack Server component 1.4 in Cisco Unified Computing System (UCS) does not properly restrict inbound access to ports, which allows remote attackers to cause a denial of service (Integrated Management Controller reboot or hang) via crafted packets, as demonstrated by nmap, aka Bug ID CSCtx19850.

Cisco Common Services, as used in Cisco Prime LAN Management Solution (LMS), Cisco Security Manager, Cisco Unified Service Monitor, and Cisco Unified Operations Manager, does not properly interact with the ActiveMQ component, which allows remote attackers to cause a denial of service (memory consumption) via simultaneous TCP sessions, aka Bug IDs CSCuh54766, CSCuh01267, CSCuh95976, and CSCuh95969.

The Secure Shell (SSH) implementation on Cisco Adaptive Security Appliances (ASA) devices, and in Cisco Firewall Services Module (FWSM), does not properly terminate sessions, which allows remote attackers to cause a denial of service (SSH service outage) by repeatedly establishing SSH connections, aka Bug IDs CSCue63881, CSCuf51892, CSCue78671, and CSCug26937.

The ITM web server in Cisco Prime Central for Hosted Collaboration Solution (HCS) allows remote attackers to cause a denial of service (temporary HTTP service outage) via a flood of TCP packets, aka Bug ID CSCuh36313.

The RIP service engine in Cisco NX-OS allows remote attackers to cause a denial of service (engine restart) via a malformed (1) RIPv4 or (2) RIPv6 message, aka Bug ID CSCtj73415.