Cisco IOS 12.2, 12.3, 12.4, 15.0, and 15.1, when the data-link switching (DLSw) feature is configured, allows remote attackers to cause a denial of service (device crash) by sending a sequence of malformed packets and leveraging a "narrow timing window," aka Bug ID CSCtf74999, a different vulnerability than CVE-2007-0199, CVE-2008-1152, and CVE-2009-0629.

Cisco IOS 12.0(32)S12 through 12.0(32)S13 and 12.0(33)S3 through 12.0(33)S4, 12.0(32)SY8 through 12.0(32)SY9, 12.2(33)SXI1 through 12.2(33)SXI2, 12.2XNC before 12.2(33)XNC2, 12.2XND before 12.2(33)XND1, and 12.4(24)T1; and IOS XE 2.3 through 2.3.1t and 2.4 through 2.4.0; when RFC4893 BGP routing is enabled, allows remote attackers to cause a denial of service (device reload) by using an RFC4271 peer to send a malformed update, aka Bug ID CSCta33973.

Cisco FWSM 3.x before 3.1(3.18), when authentication is configured to use "aaa authentication match" or "aaa authentication include", allows remote attackers to cause a denial of service (device reboot) via a malformed HTTPS request.

The (1) Airline Product Set (aka ALPS), (2) Serial Tunnel Code (aka STUN), (3) Block Serial Tunnel Code (aka BSTUN), (4) Native Client Interface Architecture (NCIA) support, (5) Data-link switching (aka DLSw), (6) Remote Source-Route Bridging (RSRB), (7) Point to Point Tunneling Protocol (PPTP), (8) X.25 for Record Boundary Preservation (RBP), (9) X.25 over TCP (XOT), and (10) X.25 Routing features in Cisco IOS 12.2 and 12.4 allows remote attackers to cause a denial of service (device reload) via a series of crafted TCP packets.

The Instant Messenger (IM) inspection engine in Cisco Adaptive Security Appliance (ASA) and Cisco PIX security appliance 7.2.x before 7.2(4), 8.0.x before 8.0(3)10, and 8.1.x before 8.1(1)2 allows remote attackers to cause a denial of service via a crafted packet.

Race condition in Cisco IOS 12.2SCH in the Performance Routing Engine (PRE) module on uBR10000 devices, when NetFlow and an MPLS IPv6 VPN are configured, allows remote attackers to cause a denial of service (PXF process crash) by sending malformed MPLS 6VPE packets quickly, aka Bug ID CSCud83396.

Cisco Digital Content Manager (DCM) 15.0.0 might allow remote ad servers to cause a denial of service (reboot) via malformed ad messages, aka Bug ID CSCur13999.

Cisco IOS 15.1(4)M2 on Cisco 1800 ISR devices, when the ISDN Basic Rate Interface is enabled, allows remote attackers to cause a denial of service (device hang) by leveraging knowledge of the ISDN phone number to trigger an interrupt timer collision during entropy collection, leading to an invalid state of the hardware encryption module, aka Bug ID CSCul77897.

Race condition in Cisco Adaptive Security Appliance (ASA) 7.0(0), 7.0(2), and 7.0(4), when running with an Active/Standby configuration and when the failover LAN interface fails, allows remote attackers to cause a denial of service (standby firewall failure) by sending spoofed ARP responses from an IP address of an active firewall, which prevents the standby firewall from becoming active, aka "failover denial of service."

Cisco 9900 Unified IP phones allow remote attackers to cause a denial of service (unregistration) via a crafted SIP header, aka Bug ID CSCul24898.

The Cisco Express Forwarding processing module in Cisco IOS XE allows remote attackers to cause a denial of service (device reload) via crafted MPLS packets that are not properly handled during IP header validation, aka Bug ID CSCuj23992.

The ScanSafe module in Cisco IOS 15.3(3)M allows remote attackers to cause a denial of service (device reload) via HTTPS packets that require tower processing, aka Bug ID CSCum97038.

The MLDP implementation in Cisco IOS 15.3(3)S and earlier on 7600 routers, when many VRFs are configured, allows remote attackers to cause a denial of service (chunk corruption and device reload) by establishing many multicast flows, aka Bug ID CSCue22345.

The VPN authentication functionality in Cisco Adaptive Security Appliance (ASA) Software allows remote attackers to cause a denial of service (device reload) by sending many username-from-cert IKE requests, aka Bug ID CSCua91108.

The IPv6 implementation in Cisco Adaptive Security Appliance (ASA) Software 9.1.3 and earlier, when NAT64 or NAT66 is enabled, does not properly process NAT rules, which allows remote attackers to cause a denial of service (device reload) via crafted packets, aka Bug ID CSCue34342.

Cisco Aironet 3600 access points allow remote attackers to cause a denial of service (memory corruption and device crash) by disrupting Cisco Wireless LAN Controller communication and consequently forcing many transitions from FlexConnect mode to Standalone mode, aka Bug ID CSCuh71210.

The HTTP server in Cisco IOS on Catalyst switches does not properly handle TCP socket events, which allows remote attackers to cause a denial of service (device crash) via crafted packets on TCP port (1) 80 or (2) 443, aka Bug ID CSCuc53853.

The regex engine in the BGP implementation in Cisco NX-OS, when a complex regular expression is configured for inbound routes, allows remote attackers to cause a denial of service (device reload) via a crafted AS path set, aka Bug ID CSCuf49554.

Array index error in the Virtual Ethernet Module (VEM) kernel driver for VMware ESXi in Cisco NX-OS on the Nexus 1000V, when STUN debugging is enabled, allows remote attackers to cause a denial of service (ESXi crash and purple screen of death) by sending crafted STUN packets to a VEM, aka Bug ID CSCud14825.

Cisco ASA CX Context-Aware Security Software allows remote attackers to cause a denial of service (device reload) via crafted TCP packets that appear to have been forwarded by a Cisco Adaptive Security Appliances (ASA) device, aka Bug ID CSCue88386.

Cisco IOS before 15.3(1)T, when media flow-around is not used, allows remote attackers to cause a denial of service (media loops and stack memory corruption) via VoIP traffic, aka Bug ID CSCub45809.

Buffer overflow in the Smart Call Home feature in the fabric interconnect in Cisco Unified Computing System (UCS) allows remote attackers to cause a denial of service by reading and forging control messages associated with Smart Call Home reports, aka Bug ID CSCtl00198.

The multicast implementation in Cisco IOS before 15.1(1)SY allows remote attackers to cause a denial of service (Route Processor crash) by sending packets at a high rate, aka Bug ID CSCts37717.

The PPP implementation in Cisco IOS 12.2 and 15.0 through 15.2, when Point-to-Point Termination and Aggregation (PTA) and L2TP are used, allows remote attackers to cause a denial of service (device crash) via crafted network traffic, aka Bug ID CSCtf71673.

Cisco IOS 15.0 and 15.1 and IOS XE 3.x do not properly handle the "set mpls experimental imposition" command, which allows remote attackers to cause a denial of service (device crash) via network traffic that triggers (1) fragmentation or (2) reassembly, aka Bug ID CSCtr56576.

Memory leak in Cisco IOS 12.4 and 15.0 through 15.2, and Cisco Unified Communications Manager (CUCM) 7.x, allows remote attackers to cause a denial of service (memory consumption) via a crafted response to a SIP SUBSCRIBE message, aka Bug IDs CSCto93837 and CSCtj61883.

A vulnerability in the handling of list headers in Cisco cBR Series Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Cisco cBR-8 Converged Broadband Routers running vulnerable versions of Cisco IOS XE are affected. More Information: CSCux40637. Known Affected Releases: 15.5(3)S 15.6(1)S. Known Fixed Releases: 15.5(3)S2 15.6(1)S1 15.6(2)S 15.6(2)SP 16.4(1).

The HTTP client in Cisco IOS 12.4 and 15.0 allows user-assisted remote attackers to cause a denial of service (device crash) via a malformed HTTP response to a request for service installation, aka Bug ID CSCts12249.

Race condition on Cisco Adaptive Security Appliances (ASA) devices allows remote attackers to cause a denial of service (CPU consumption or device reload) by establishing multiple connections, leading to improper handling of hash lookups for secondary flows, aka Bug IDs CSCue31622 and CSCuc71272.

Cisco IOS XE 3.7S(.1) and earlier allows remote attackers to cause a denial of service (Packet Processor crash) via fragmented MPLS IP packets, aka Bug ID CSCul00709.

The ethernet-lldp component in Cisco IOS 12.2 before 12.2(33)SXJ1 does not properly support a large number of LLDP Management Address (MA) TLVs, which allows remote attackers to cause a denial of service (device crash) via crafted LLDPDUs, aka Bug ID CSCtj22354.

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.

CallManager Express (CME) on Cisco IOS before 15.0(1)XA1 does not properly handle SIP TRUNK traffic that contains rate bursts and a "peculiar" request size, which allows remote attackers to cause a denial of service (memory consumption) by sending this traffic over a long duration, aka Bug ID CSCtb47950.

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 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 networking component of Cisco access point (AP) software could allow an unauthenticated, remote attacker to cause a temporary disruption of service. This vulnerability is due to overuse of AP resources. An attacker could exploit this vulnerability by connecting to an AP on an affected device as a wireless client and sending a high rate of traffic over an extended period of time. A successful exploit could allow the attacker to cause the Datagram TLS (DTLS) session to tear down and reset, causing a denial of service (DoS) condition.

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 Vector Packet Processor (VPP) of Cisco Packet Data Network Gateway (PGW) could allow an unauthenticated, remote attacker to stop ICMP traffic from being processed over an IPsec connection. This vulnerability is due to the VPP improperly handling a malformed packet. An attacker could exploit this vulnerability by sending a malformed Encapsulating Security Payload (ESP) packet over an IPsec connection. A successful exploit could allow the attacker to stop ICMP traffic over an IPsec connection and cause a denial of service (DoS).

A vulnerability in a logging API in Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to cause the device to become unresponsive or trigger an unexpected reload. This vulnerability could also allow an attacker with valid user credentials, but not Administrator privileges, to view a system log file that they would not normally have access to. This vulnerability is due to a lack of rate-limiting of requests that are sent to a specific API that is related to an FMC log. An attacker could exploit this vulnerability by sending a high rate of HTTP requests to the API. A successful exploit could allow the attacker to cause a denial of service (DoS) condition due to the FMC CPU spiking to 100 percent utilization or to the device reloading. CPU utilization would return to normal if the attack traffic was stopped before an unexpected reload was triggered.

A vulnerability in the DNS inspection handler of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service condition (DoS) on an affected device. This vulnerability is due to a lack of proper processing of incoming requests. An attacker could exploit this vulnerability by sending crafted DNS requests at a high rate to an affected device. A successful exploit could allow the attacker to cause the device to stop responding, resulting in a DoS condition.

A vulnerability in the local interface of Cisco BroadWorks Network Server could allow an unauthenticated, remote attacker to exhaust system resources, causing a denial of service (DoS) condition. This vulnerability exists because rate limiting does not occur for certain incoming TCP connections. An attacker could exploit this vulnerability by sending a high rate of TCP connections to the server. A successful exploit could allow the attacker to cause TCP connection resources to grow rapidly until the Cisco BroadWorks Network Server becomes unusable. Note: To recover from this vulnerability, either Cisco BroadWorks Network Server software must be restarted or the Cisco BroadWorks Network Server node must be rebooted. For more information, see the section of this advisory. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

A vulnerability in Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of certain TLS connections that are processed by an affected device. An attacker could exploit this vulnerability by establishing a large number of concurrent TLS connections to an affected device. A successful exploit could allow the attacker to cause the device to drop new TLS email messages that come from the associated email servers. Exploitation of this vulnerability does not cause the affected device to unexpectedly reload. The device will recover autonomously within a few hours of when the attack is halted or mitigated.

A vulnerability in Cisco Smart Software Manager On-Prem (SSM On-Prem) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to incorrect handling of multiple simultaneous device registrations on Cisco SSM On-Prem. An attacker could exploit this vulnerability by sending multiple device registration requests to Cisco SSM On-Prem. A successful exploit could allow the attacker to cause a DoS condition on an affected device.

A vulnerability in an API endpoint of multiple Cisco Unified Communications Products could allow an unauthenticated, remote attacker to cause high CPU utilization, which could impact access to the web-based management interface and cause delays with call processing. This API is not used for device management and is unlikely to be used in normal operations of the device. This vulnerability is due to improper API authentication and incomplete validation of the API request. An attacker could exploit this vulnerability by sending a crafted HTTP request to a specific API on the device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition due to high CPU utilization, which could negatively impact user traffic and management access. When the attack stops, the device will recover without manual intervention.

A vulnerability in the Cisco Fabric Services over IP (CFSoIP) feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of incoming CFSoIP packets. An attacker could exploit this vulnerability by sending crafted CFSoIP packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

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 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 packet processing functionality of Cisco access point (AP) software could allow an unauthenticated, adjacent attacker to exhaust resources on an affected device.  This vulnerability is due to insufficient management of resources when handling certain types of traffic. An attacker could exploit this vulnerability by sending a series of specific wireless packets to an affected device. A successful exploit could allow the attacker to consume resources on an affected device. A sustained attack could lead to the disruption of the Control and Provisioning of Wireless Access Points (CAPWAP) tunnel and intermittent loss of wireless client traffic.

A vulnerability in the Split DNS feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability occurs because the regular expression (regex) engine that is used with the Split DNS feature of affected releases may time out when it processes the DNS name list configuration. An attacker could exploit this vulnerability by trying to resolve an address or hostname that the affected device handles. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.