The DHCP relay agent in Cisco Adaptive Security Appliance (ASA) and PIX 7.2 allows remote attackers to cause a denial of service (dropped packets) via a DHCPREQUEST or DHCPINFORM message that causes multiple DHCPACK messages to be sent from DHCP servers to the agent, which consumes the memory allocated for a local buffer. NOTE: this issue only occurs when multiple DHCP servers are used.

A vulnerability in the IPv6 traffic processing of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an unexpected restart of the netstack process on an affected device. The vulnerability is due to improper validation of IPv6 traffic sent through an affected device. An attacker could exploit this vulnerability by sending a malformed IPv6 packet through an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition while the netstack process restarts. A sustained attack could lead to a reboot of the device.

The web framework on Cisco Web Security Appliance (WSA), Email Security Appliance (ESA), and Content Security Management Appliance (SMA) devices does not properly manage the state of HTTP and HTTPS sessions, which allows remote attackers to cause a denial of service (management GUI outage) via multiple TCP connections, aka Bug IDs CSCuj59411, CSCuf89818, and CSCuh05635.

Linux kernel versions 4.9+ can be forced to make very expensive calls to tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() for every incoming packet which can lead to a denial of service.

The TCP reassembly feature in Cisco IOS XE 3.7 before 3.7.3S and 3.8 before 3.8.1S on 1000 ASR devices allows remote attackers to cause a denial of service (device reload) via large TCP packets that are processed by the (1) NAT or (2) ALG component, aka Bug ID CSCud72509.

Race condition in the IPv6 virtual fragmentation reassembly (VFR) implementation in Cisco IOS 12.2 through 12.4 and 15.0 through 15.3 allows remote attackers to cause a denial of service (device reload or hang) via fragmented IPv6 packets, aka Bug ID CSCud64812.

Cisco IOS 12.4 and earlier, when using the crypto packages and SSL support is enabled, allows remote attackers to cause a denial of service via a malformed (1) ClientHello, (2) ChangeCipherSpec, or (3) Finished message during an SSL session.

The SIP implementation in Cisco TelePresence TC Software 4.x and TE Software 4.x allows remote attackers to cause a denial of service (device reload) via crafted SIP packets, aka Bug ID CSCto70562.

A vulnerability in the Cisco Fabric Services component of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause process crashes, which can result in a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient validation of TCP packets when processed by the Cisco Fabric Services over IP (CFSoIP) feature. An attacker could exploit this vulnerability by sending a malicious Cisco Fabric Services TCP packet to an affected device. A successful exploit could allow the attacker to cause process crashes, resulting in a device reload and a DoS condition. Note: There are three distribution methods that can be configured for Cisco Fabric Services. This vulnerability affects only distribution method CFSoIP, which is disabled by default. See the Details section for more information.

Cisco Firewall Services Module (FWSM) 3.x before 3.1(3.11), when the HTTPS server is enabled, allows remote attackers to cause a denial of service (device reboot) via certain HTTPS traffic.

Cisco IOS XE 3.4 before 3.4.5S, and 3.5 through 3.7 before 3.7.1S, on 1000 series Aggregation Services Routers (ASR) does not properly implement the Cisco Multicast Leaf Recycle Elimination (MLRE) feature, which allows remote attackers to cause a denial of service (card reload) via fragmented IPv6 MVPN (aka MVPNv6) packets, aka Bug ID CSCub34945, a different vulnerability than CVE-2013-1164.

Cisco Prime Central for Hosted Collaboration Solution (HCS) Assurance 8.6 and 9.x before 9.2(1) allows remote attackers to cause a denial of service (memory consumption) via a flood of TCP packets to port 44444, aka Bug ID CSCtz92776.

The IDSM-2 drivers in Cisco Intrusion Prevention System (IPS) Software on Cisco Catalyst 6500 devices with an IDSM-2 module allow remote attackers to cause a denial of service (device hang) via malformed IPv4 TCP packets, aka Bug ID CSCuh27460.

The Next-Generation Firewall (aka NGFW, formerly CX Context-Aware Security) module 9.x before 9.1.1.9 and 9.1.2.x before 9.1.2.12 for Cisco Adaptive Security Appliances (ASA) devices allows remote attackers to cause a denial of service (device reload or traffic-processing outage) via fragmented (1) IPv4 or (2) IPv6 traffic, aka Bug ID CSCue88387.

Memory leak in Cisco Unified Communications Manager (Unified CM) 8.5(x) before 8.5(1)su6, 8.6(x) before 8.6(2a)su3, and 9.x before 9.1(1) allows remote attackers to cause a denial of service (service disruption) via a high rate of UDP packets, aka Bug ID CSCub85597.

The Cisco Unified IP Phone 8945 with software 9.3(2) allows remote attackers to cause a denial of service (device hang) via a malformed PNG file, aka Bug ID CSCud04270.

Cisco Adaptive Security Appliance (ASA) Software 8.4.x before 8.4(3) and 8.6.x before 8.6(1.3) does not properly manage memory upon an AnyConnect SSL VPN client disconnection, which allows remote attackers to cause a denial of service (memory consumption, and forwarding outage or system hang) via packets to the disconnected machine's IP address, aka Bug ID CSCtt36737.

Cisco Intrusion Prevention System (IPS) Software on IPS NME devices before 7.0(9)E4 allows remote attackers to cause a denial of service (device reload) via malformed IPv4 packets that trigger incorrect memory allocation, aka Bug ID CSCua61977.

The management GUI in the web framework in IronPort AsyncOS on Cisco Web Security Appliance devices before 7.1.3-013, 7.5 before 7.5.0-838, and 7.7 before 7.7.0-602; Email Security Appliance devices before 7.1.5-106 and 7.3, 7.5, and 7.6 before 7.6.3-019; and Content Security Management Appliance devices before 7.9.1-102 and 8.0 before 8.0.0-404 allows remote attackers to cause a denial of service (system hang) via a series of (1) HTTP or (2) HTTPS requests to a management interface, aka Bug IDs CSCzv58669, CSCzv63329, and CSCzv78669.

Memory leak in Cisco Unified Communications Manager IM and Presence Service before 8.6(5)SU1 and 9.x before 9.1(2), and Cisco Unified Presence, allows remote attackers to cause a denial of service (memory and CPU consumption) by making many TCP connections to port (1) 5060 or (2) 5061, aka Bug ID CSCud84959.

The IronPort Spam Quarantine (ISQ) component in the web framework in IronPort AsyncOS on Cisco Email Security Appliance devices before 7.1.5-106 and 7.3, 7.5, and 7.6 before 7.6.3-019 and Content Security Management Appliance devices before 7.9.1-102 and 8.0 before 8.0.0-404 allows remote attackers to cause a denial of service (service crash or hang) via a high rate of TCP connection attempts, aka Bug IDs CSCzv25573 and CSCzv81712.

Cisco Prime Central for Hosted Collaboration Solution (HCS) Assurance 8.6 and 9.x before 9.2(1) allows remote attackers to cause a denial of service (memory consumption) via a flood of TCP packets to port (1) 61615 or (2) 61616, aka Bug ID CSCtz90114.

Cisco TelePresence TC Software before 5.1.7 and TE Software before 4.1.3 allow remote attackers to cause a denial of service (device reload) via crafted SIP packets, aka Bug ID CSCue01743.

Cisco Unified Communications Manager (Unified CM) 7.1(x) before 7.1(5b)su6a does not properly handle errors, which allows remote attackers to cause a denial of service (service disruption) via malformed registration messages, aka Bug ID CSCuf93466.

Cisco Prime Central for Hosted Collaboration Solution (HCS) Assurance 8.6 and 9.x before 9.2(1) allows remote attackers to cause a denial of service (disk consumption) via a flood of TCP packets to port 5400, leading to large error-log files, aka Bug ID CSCua42724.

A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause the CPU utilization to increase to 100 percent, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of email messages that contain large attachments. An attacker could exploit this vulnerability by sending a malicious email message through the targeted device. A successful exploit could allow the attacker to cause a permanent DoS condition due to high CPU utilization. This vulnerability may require manual intervention to recover the ESA.

Memory leak in the IKEv1 implementation in Cisco IOS 15.1 allows remote attackers to cause a denial of service (memory consumption) via unspecified (1) IPv4 or (2) IPv6 IKE packets, aka Bug ID CSCth81055.

Cisco TelePresence Supervisor MSE 8050 before 2.3(1.31) allows remote attackers to cause a denial of service (CPU consumption or device reload) by establishing TCP connections at a high rate, aka Bug IDs CSCuf76076 and CSCuf79763.

The authentication-proxy implementation on Cisco Adaptive Security Appliances (ASA) devices with software 7.x before 7.2(5.10), 8.0 before 8.0(5.31), 8.1 and 8.2 before 8.2(5.38), 8.3 before 8.3(2.37), 8.4 before 8.4(5.3), 8.5 and 8.6 before 8.6(1.10), 8.7 before 8.7(1.4), 9.0 before 9.0(1.1), and 9.1 before 9.1(1.2) allows remote attackers to cause a denial of service (device reload) via a crafted URL, aka Bug ID CSCud16590.

The General Responder implementation in the IP Service Level Agreement (SLA) feature in Cisco IOS 15.2 and IOS XE 3.1.xS through 3.4.xS before 3.4.5S and 3.5.xS through 3.7.xS before 3.7.2S allows remote attackers to cause a denial of service (device reload) via crafted (1) IPv4 or (2) IPv6 IP SLA packets on UDP port 1167, aka Bug ID CSCuc72594.

The auth-proxy functionality in Cisco Firewall Services Module (FWSM) software 3.1 and 3.2 before 3.2(20.1), 4.0 before 4.0(15.2), and 4.1 before 4.1(5.1) allows remote attackers to cause a denial of service (device reload) via a crafted URL, aka Bug ID CSCtg02624.

Cisco Unified Presence Server (CUPS) 8.6, 9.0, and 9.1 before 9.1.1 allows remote attackers to cause a denial of service (CPU consumption) via crafted packets to the SIP TCP port, aka Bug ID CSCua89930.

The Wireless Intrusion Prevention System (wIPS) component on Cisco Wireless LAN Controller (WLC) devices with software 7.0 before 7.0.235.0, 7.1 and 7.2 before 7.2.110.0, and 7.3 before 7.3.101.0 allows remote attackers to cause a denial of service (device reload) via crafted IP packets, aka Bug ID CSCtx80743.

Cisco NX-OS on Nexus 5500 devices 4.x and 5.x before 5.0(3)N2(2), Nexus 3000 devices 5.x before 5.0(3)U3(2), and Unified Computing System (UCS) 6200 devices before 2.0(1w) allows remote attackers to cause a denial of service (device reload) by sending a jumbo packet to the management interface, aka Bug IDs CSCtx17544, CSCts10593, and CSCtx95389.

Cisco Unified Communications Manager (CUCM) 8.6 before 8.6(2a)su2, 8.6 BE3k before 8.6(4) BE3k, and 9.x before 9.0(1) allows remote attackers to cause a denial of service (CPU consumption and GUI and voice outages) via malformed packets to unused UDP ports, aka Bug ID CSCtx43337.

Cisco IOS XE 3.2 through 3.4 before 3.4.5S, and 3.5 through 3.7 before 3.7.1S, on 1000 series Aggregation Services Routers (ASR), when VRF-aware NAT and SIP ALG are enabled, allows remote attackers to cause a denial of service (card reload) by sending many SIP packets, aka Bug ID CSCuc65609.

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

Cisco IOS XE 2.x and 3.x before 3.4.5S, and 3.5 through 3.7 before 3.7.1S, on 1000 series Aggregation Services Routers (ASR) allows remote attackers to cause a denial of service (card reload) by sending many crafted L2TP packets, aka Bug ID CSCtz23293.

A vulnerability in the Network Address Translation 64 (NAT64) functions of Cisco IOS Software could allow an unauthenticated, remote attacker to cause either an interface queue wedge or a device reload. The vulnerability is due to the incorrect handling of certain IPv4 packet streams that are sent through the device. An attacker could exploit this vulnerability by sending specific IPv4 packet streams through the device. An exploit could allow the attacker to either cause an interface queue wedge or a device reload, resulting in a denial of service (DoS) condition.

The CallServer component in Cisco Unified Customer Voice Portal (CVP) Software before 9.0.1 ES 11 allows remote attackers to cause a denial of service (call-acceptance outage) via malformed SIP INVITE messages, aka Bug ID CSCua65148.

A vulnerability in the implementation of the Lightweight Directory Access Protocol (LDAP) feature in Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerabilities are due to the improper parsing of LDAP packets sent to an affected device. An attacker could exploit these vulnerabilities by sending a crafted LDAP packet, using Basic Encoding Rules (BER), to be processed by an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Cisco Wireless LAN Controller (WLC) devices with software 7.0 before 7.0.220.0, 7.1 before 7.1.91.0, and 7.2 before 7.2.103.0 allow remote attackers to cause a denial of service (Access Point reload) via crafted SIP packets, aka Bug ID CSCts87659.

Cisco Adaptive Security Appliances (ASA) devices with software 7.x before 7.2(5.10), 8.0 before 8.0(5.28), 8.1 and 8.2 before 8.2(5.35), 8.3 before 8.3(2.34), 8.4 before 8.4(4.11), 8.6 before 8.6(1.10), and 8.7 before 8.7(1.3), and Cisco Firewall Services Module (FWSM) software 3.1 and 3.2 before 3.2(24.1) and 4.0 and 4.1 before 4.1(11.1), allow remote attackers to cause a denial of service (device reload) via a crafted IKEv1 message, aka Bug IDs CSCub85692 and CSCud20267.

Cisco Adaptive Security Appliances (ASA) devices with software 9.0 before 9.0(1.2) allow remote attackers to cause a denial of service (device reload) via a crafted field in a DNS message, aka Bug ID CSCuc80080.

Cisco IOS XE 3.4 before 3.4.4S, 3.5, and 3.6 on 1000 series Aggregation Services Routers (ASR) does not properly implement the Cisco Multicast Leaf Recycle Elimination (MLRE) feature, which allows remote attackers to cause a denial of service (card reload) via fragmented IPv6 multicast packets, aka Bug ID CSCtz97563.

The Smart Install client functionality in Cisco IOS 12.2 and 15.0 through 15.3 on Catalyst switches allows remote attackers to cause a denial of service (device reload) via crafted image list parameters in Smart Install packets, aka Bug ID CSCub55790.

Race condition in the VRF-aware NAT feature in Cisco IOS 12.2 through 12.4 and 15.0 through 15.2 allows remote attackers to cause a denial of service (memory consumption) via IPv4 packets, aka Bug IDs CSCtg47129 and CSCtz96745.

The IP stack in Cisco Intrusion Prevention System (IPS) Software in ASA 5500-X IPS-SSP software and hardware modules before 7.1(5)E4, IPS 4500 sensors before 7.1(6)E4, and IPS 4300 sensors before 7.1(5)E4 allows remote attackers to cause a denial of service (MainApp process hang) via malformed IPv4 packets, aka Bug ID CSCtx18596.

The management API in the XML API management service in the Manager component in Cisco Unified Computing System (UCS) 1.x before 1.2(1b) allows remote attackers to cause a denial of service (service outage) via a malformed request, aka Bug ID CSCtg48206.

The Protocol Translation (PT) functionality in Cisco IOS 12.3 through 12.4 and 15.0 through 15.3, when one-step port-23 translation or a Telnet-to-PAD ruleset is configured, does not properly validate TCP connection information, which allows remote attackers to cause a denial of service (device reload) via an attempted connection to a PT resource, aka Bug ID CSCtz35999.