A vulnerability in the H.264 decoder function of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a Cisco Meeting Server media process to restart unexpectedly when it receives an illegal H.264 frame. The vulnerability is triggered by an H.264 frame that has an invalid picture parameter set (PPS) value. An attacker could exploit this vulnerability by sending a malformed H.264 frame to the targeted device. An exploit could allow the attacker to cause a denial of service (DoS) condition because the media process could restart. The media session should be re-established within a few seconds, during which there could be a brief interruption in service. Cisco Bug IDs: CSCvg12559.

A vulnerability in Cisco WebEx Meetings Server could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient limitations on the number of connections that can be made to the affected software. An attacker could exploit this vulnerability by opening multiple connections to the server and exhausting server resources. A successful exploit could cause the server to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvf41006.

A vulnerability in the implementation of Session Initiation Protocol (SIP) functionality in Cisco Small Business SPA51x Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to become unresponsive, resulting in a denial of service (DoS) condition. The vulnerability is due to the improper handling of SIP request messages by an affected device. An attacker could exploit this vulnerability by sending malformed SIP messages to an affected device. A successful exploit could allow the attacker to cause the affected device to become unresponsive, resulting in a DoS condition that persists until the device is restarted manually. This vulnerability affects Cisco Small Business SPA51x Series IP Phones that are running Cisco SPA51x Firmware Release 7.6.2SR1 or earlier. Cisco Bug IDs: CSCvc63982.

A vulnerability in the implementation of Session Initiation Protocol (SIP) functionality in Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to become unresponsive, resulting in a denial of service (DoS) condition. The vulnerability is due to the improper handling of SIP request messages by an affected device. An attacker could exploit this vulnerability by using formatted specifiers in a SIP payload that is sent to an affected device. A successful exploit could allow the attacker to cause the affected device to become unresponsive, resulting in a DoS condition that persists until the device is restarted manually. This vulnerability affects Cisco Small Business SPA50x, SPA51x, and SPA52x Series IP Phones that are running firmware release 7.6.2SR1 or earlier. Cisco Bug IDs: CSCvc63986.

A vulnerability in the gRPC code of Cisco IOS XR Software for Cisco Network Convergence System (NCS) 5500 Series Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition when the emsd service stops. The vulnerability is due to the software's inability to process HTTP/2 packets. An attacker could exploit this vulnerability by sending a malformed HTTP/2 frame to the affected device. A successful exploit could allow the attacker to create a DoS condition when the emsd service stops. Cisco Bug IDs: CSCvb99388.

A vulnerability in the HTTP web interface for Cisco Wide Area Application Services (WAAS) could allow an unauthenticated, remote attacker to cause an HTTP Application Optimization (AO) related process to restart, causing a partial denial of service (DoS) condition. The vulnerability is due to lack of input validation of user-supplied input parameters within an HTTP request. An attacker could exploit this vulnerability by sending a crafted HTTP request through the targeted device. An exploit could allow the attacker to cause a DoS condition due to a process unexpectedly restarting. The WAAS could drop traffic during the brief time the process is restarting. Cisco Bug IDs: CSCvc63048.

A vulnerability in SSL traffic decryption for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause depletion of system memory, aka a Firepower Detection Engine SSL Decryption Memory Consumption Denial of Service vulnerability. If this memory leak persists over time, a denial of service (DoS) condition could develop because traffic can cease to be forwarded through the device. The vulnerability is due to an error in how the Firepower Detection Snort Engine handles SSL traffic decryption and notifications to and from the Adaptive Security Appliance (ASA) handler. An attacker could exploit this vulnerability by sending a steady stream of malicious Secure Sockets Layer (SSL) traffic through the device. An exploit could allow the attacker to cause a DoS condition when the device runs low on system memory. This vulnerability affects Cisco Firepower Threat Defense (FTD) Software Releases 6.0.1 and later, running on any of the following Cisco products: Adaptive Security Appliance (ASA) 5500-X Series Next-Generation Firewalls, Firepower 2100 Series Security Appliances, Firepower 4100 Series Security Appliances, Firepower 9300 Series Security Appliances. Cisco Bug IDs: CSCve02069.

A vulnerability in the Independent Computing Architecture (ICA) accelerator feature for the Cisco Wide Area Application Services (WAAS) could allow an unauthenticated, remote attacker to cause an ICA application optimization-related process to restart, resulting in a partial denial of service (DoS) condition. The vulnerability is due to improperly aborting a connection when an unexpected protocol packet is received. An attacker could exploit this vulnerability by sending a crafted ICA traffic through the targeted device. A successful exploit could allow the attacker to cause a DoS condition that is due to a process unexpectedly restarting. The Cisco WAAS could drop ICA traffic while the process is restarting. This vulnerability affects Cisco Wide Area Application Services (WAAS) and Cisco Virtual Wide Area Application Services (vWAAS). Cisco Bug IDs: CSCve74457.

A vulnerability in the General Packet Radio Service (GPRS) Tunneling Protocol ingress packet handler of Cisco ASR 5500 System Architecture Evolution (SAE) Gateways could allow an unauthenticated, remote attacker to cause a partial denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation of GPRS Tunneling Protocol packet headers. An attacker could exploit this vulnerability by sending a malformed GPRS Tunneling Protocol packet to an affected device. A successful exploit could allow the attacker to cause the GTPUMGR process on an affected device to restart unexpectedly, resulting in a partial DoS condition. If the GTPUMGR process restarts, there could be a brief impact on traffic passing through the device. Cisco Bug IDs: CSCve07119.

A vulnerability in Session Initiation Protocol (SIP) call handling in Cisco IP Phone 8800 Series devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition because the SIP process unexpectedly restarts. All active phone calls are dropped as the SIP process restarts. The vulnerability is due to incomplete input validation of the SIP packet header. An attacker could exploit this vulnerability by sending a malformed SIP packet to a targeted phone. An exploit could allow the attacker to cause a DoS condition because all phone calls are dropped when the SIP process unexpectedly restarts. Cisco Bug IDs: CSCvc62590.

A vulnerability in the detection engine parsing of IPv6 packets for Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause high CPU utilization or to cause a denial of service (DoS) condition because the Snort process restarts unexpectedly. The vulnerability is due to improper input validation of the fields in the IPv6 extension header packet. An attacker could exploit this vulnerability by sending a malicious IPv6 packet 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. This vulnerability is specific to IPv6 traffic only. This vulnerability affects Cisco Firepower System Software Releases 6.0 and later when the software has one or more file action policies configured and is running on any of the following Cisco products: 3000 Series Industrial Security Appliances (ISR), Adaptive Security Appliance (ASA) 5500-X Series with FirePOWER Services, Adaptive Security Appliance (ASA) 5500-X Series Next-Generation Firewalls, Advanced Malware Protection (AMP) for Networks, 7000 Series Appliances, Advanced Malware Protection (AMP) for Networks, 8000 Series Appliances, FirePOWER 7000 Series Appliances, FirePOWER 8000 Series Appliances, Firepower Threat Defense for Integrated Services Routers (ISRs), Firepower 2100 Series Security Appliances, Firepower 4100 Series Security Appliances, Firepower 9300 Series Security Appliances, Virtual Next-Generation Intrusion Prevention System (NGIPSv) for VMware. Cisco Bug IDs: CSCvd34776.

The SIP implementation in Cisco IOS 15.5(3)M on Cisco Unified Border Element (CUBE) devices allows remote attackers to cause a denial of service via crafted SIP messages, aka Bug ID CSCuv79202.

The Data-link Switching (DLSw) feature in Cisco IOS 11.0 through 12.4 allows remote attackers to cause a denial of service (device reload) via "an invalid value in a DLSw message... during the capabilities exchange."

The DHCPv6 server in Cisco IOS on ASR 9000 devices with software 5.2.0 Base allows remote attackers to cause a denial of service (process reset) via crafted packets, aka Bug ID CSCun36525.

A vulnerability in the TCP state machine of Cisco RF Gateway 1 devices could allow an unauthenticated, remote attacker to prevent an affected device from delivering switched digital video (SDV) or video on demand (VoD) streams, resulting in a denial of service (DoS) condition. The vulnerability is due to a processing error with TCP connections to the affected device. An attacker could exploit this vulnerability by establishing a large number of TCP connections to an affected device and not actively closing those TCP connections. A successful exploit could allow the attacker to prevent the affected device from delivering SDV or VoD streams to set-top boxes. Cisco Bug IDs: CSCvf19887.

A vulnerability in the Multi-Pod or Multi-Site network configurations for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to unexpectedly restart the device, resulting in a denial of service (DoS) condition. This vulnerability exists because TCP traffic sent to a specific port on an affected device is not properly sanitized. An attacker could exploit this vulnerability by sending crafted TCP data to a specific port that is listening on a public-facing IP address for the Multi-Pod or Multi-Site configuration. A successful exploit could allow the attacker to cause the device to restart unexpectedly, resulting in a DoS condition.

Cisco IP Phones 7902/7905/7912, ATA 186/188, Unity Express, ACNS, and Subscriber Edge Services Manager (SESM) allows remote attackers to cause a denial of service (crash or instability) via a compressed DNS packet with a label length byte with an incorrect offset.

The Web Management GUI on Cisco Wireless LAN Controller (WLC) devices with software 7.4(140.0) and 8.0(120.0) allows remote attackers to cause a denial of service (client disconnection) via unspecified vectors, aka Bug ID CSCuw10610.

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.

Cisco 2611 router running IOS 12.1(6.5), possibly an interim release, allows remote attackers to cause a denial of service via port scans such as (1) scanning all ports on a single host and (2) scanning a network of hosts for a single open port through the router. NOTE: the vendor could not reproduce this issue, saying that the original reporter was using an interim release of the software.

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.

Cisco CallManager (CCM) 3.2 and earlier, 3.3 before 3.3(5), 4.0 before 4.0(2a)SR2b, and 4.1 4.1 before 4.1(3)SR1 allows remote attackers to cause a denial of service (memory consumption and restart) via crafted packets to (1) the CTI Manager (ctimgr.exe) or (2) the CallManager (ccm.exe).

Cisco IOS 12.0S through 12.3YH allows remote attackers to cause a denial of service (device restart) via a crafted IPv6 packet.

Cisco IOS 12.0 through 12.3YL, with BGP enabled and running the bgp log-neighbor-changes command, allows remote attackers to cause a denial of service (device reload) via a malformed BGP packet.

Cisco VPN 3000 Concentrator 2.2.x, 3.6(Rel), and 3.x before 3.5.5, allows remote attackers to cause a denial of service via (1) malformed or (2) large ISAKMP packets.

Cisco Virtual Private Network (VPN) Client software 2.x.x and 3.x before 3.0.5 allows remote attackers to cause a denial of service (crash) via TCP packets with source and destination ports of 137 (NETBIOS).

A vulnerability in the data acquisition (DAQ) component of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured access control policies or cause a denial of service (DoS) condition. The vulnerability exists because the affected software improperly manages system memory resources when inspecting traffic. An attacker could exploit this vulnerability by generating specific traffic patterns for the software to inspect. A successful exploit could allow the attacker to exhaust system memory resources used for traffic inspection. Depending on the configuration, the FTD Software could fail open and cease to inspect traffic or fail closed and result in a DoS condition. This vulnerability may require manual intervention to restore the software.

Cisco Virtual Private Network (VPN) Client 3.5.4 and earlier allows remote attackers to cause a denial of service (CPU consumption) via a packet with a zero-length payload.

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.

Cisco Unified Communications Domain Manager allows remote attackers to cause a denial of service (CPU consumption) via a flood of malformed UDP packets, aka Bug ID CSCug47057.

Cisco Catalyst 5000 series switches 6.1(2) and earlier will forward an 802.1x frame on a Spanning Tree Protocol (STP) blocked port, which causes a network storm and a denial of service.

A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an NX-API system process to unexpectedly restart. The vulnerability is due to incorrect validation of the HTTP header of a request that is sent to the NX-API. An attacker could exploit this vulnerability by sending a crafted HTTP request to the NX-API on an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition in the NX-API service; however, the NX-OS device itself would still be available and passing network traffic. Note: The NX-API feature is disabled by default.

A vulnerability in the web-based management interface of Cisco RV110W, RV130W, and RV215W Routers could allow an unauthenticated, remote attacker to disconnect clients that are connected to the guest network on an affected router. The vulnerability is due to improper authorization of an HTTP request. An attacker could exploit this vulnerability by accessing the URL for device disconnection and providing the connected device information. A successful exploit could allow the attacker to deny service to specific clients that are connected to the guest network.

A vulnerability in the Session Initiation Protocol (SIP) protocol implementation of Cisco Unified Communications Manager could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation of input SIP traffic. An attacker could exploit this vulnerability by sending a malformed SIP packet to an affected Cisco Unified Communications Manager. A successful exploit could allow the attacker to trigger a new registration process on all connected phones, temporarily disrupting service.

The hamgr service in the IPv6 Proxy Mobile (PM) implementation in Cisco StarOS 18.1.0.59776 on ASR 5000 devices allows remote attackers to cause a denial of service (service reload and call-processing outage) via malformed PM packets, aka Bug ID CSCut94711.

A vulnerability in the Simple Network Management Protocol (SNMP) input packet processor of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause the SNMP application to leak system memory, which could cause an affected device to restart unexpectedly. The vulnerability is due to improper error handling when processing inbound SNMP packets. An attacker could exploit this vulnerability by sending multiple crafted SNMP packets to an affected device. A successful exploit could allow the attacker to cause the SNMP application to leak system memory because of an improperly handled error condition during packet processing. Over time, this memory leak could cause the SNMP application to restart multiple times, leading to a system-level restart and a denial of service (DoS) condition.

A vulnerability in the Secure Sockets Layer (SSL) input packet processor of Cisco Small Business 200, 300, and 500 Series Managed Switches could allow an unauthenticated, remote attacker to cause a memory corruption on an affected device. The vulnerability is due to improper validation of HTTPS packets. An attacker could exploit this vulnerability by sending a malformed HTTPS packet to the management web interface of the affected device. A successful exploit could allow the attacker to cause an unexpected reload of the device, resulting in a denial of service (DoS) condition.

A vulnerability in the authentication service of the Cisco Unified Communications Manager IM and Presence (Unified CM IM&P) Service, Cisco TelePresence Video Communication Server (VCS), and Cisco Expressway Series could allow an unauthenticated, remote attacker to cause a service outage for users attempting to authenticate, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient controls for specific memory operations. An attacker could exploit this vulnerability by sending a malformed Extensible Messaging and Presence Protocol (XMPP) authentication request to an affected system. A successful exploit could allow the attacker to cause an unexpected restart of the authentication service, preventing users from successfully authenticating. Exploitation of this vulnerability does not impact users who were authenticated prior to an attack.

Cisco Catalyst 6000, 5000, or 4000 switches allow remote attackers to cause a denial of service by connecting to the SSH service with a non-SSH client, which generates a protocol mismatch error.

A vulnerability in the web interface of Cisco Small Business 200, 300, and 500 Series Managed 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 validation of requests sent to the web interface. An attacker could exploit this vulnerability by sending a malicious request to the web interface of an affected device. A successful exploit could allow the attacker to cause an unexpected reload of the device, resulting in a DoS condition.