The web management interface for Cisco Content Service Switch (CSS) 11000 switches allows remote attackers to cause a denial of service (soft reset) via (1) an HTTPS POST request, or (2) malformed XML data.

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.

Buffer overflows in Cisco Virtual Private Network (VPN) Client 3.5.4 and earlier allows remote attackers to cause a denial of service via (1) an Internet Key Exchange (IKE) with a large Security Parameter Index (SPI) payload, or (2) an IKE packet with a large number of valid payloads.

Cisco routers and switches running IOS 12.0 through 12.2.1 allows a remote attacker to cause a denial of service via a flood of UDP packets.

Cisco IOS 12.2 and earlier running Cisco Discovery Protocol (CDP) allows remote attackers to cause a denial of service (memory consumption) via a flood of CDP neighbor announcements.

Cisco CBOS 2.3.8 and earlier allows remote attackers to cause a denial of service via an ICMP ECHO REQUEST (ping) with the IP Record Route option set.

Web-based configuration utility in Cisco 600 series routers running CBOS 2.0.1 through 2.4.2ap binds itself to port 80 even when web-based configuration services are disabled, which could leave the router open to attack.

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.

Cisco CBOS 2.3.8 and earlier allows remote attackers to cause a denial of service via a series of large ICMP ECHO REPLY (ping) packets, which cause it to enter ROMMON mode and stop forwarding packets.

Cisco VPN 3000 series concentrators before 2.5.2(F) allow remote attackers to cause a denial of service via an IP packet with an invalid IP option.

Cisco IOS 11.x and 12.0 with ATM support allows attackers to cause a denial of service via the undocumented Interim Local Management Interface (ILMI) SNMP community string.

Multiple Cisco networking products allow remote attackers to cause a denial of service on the local network via a series of ARP packets sent to the router's interface that contains a different MAC address for the router, which eventually causes the router to overwrite the MAC address in its ARP table.

Cisco IOS 12.1(2)T, 12.1(3)T allow remote attackers to cause a denial of service (reload) via a connection to TCP ports 3100-3999, 5100-5999, 7100-7999 and 10100-10999.

Cisco devices IOS 12.0 and earlier allow a remote attacker to cause a crash, or bad route updates, via malformed BGP updates with unrecognized transitive attribute.

Cisco 600 routers running CBOS 2.4.1 and earlier allow remote attackers to cause a denial of service via a large ICMP echo (ping) packet.

Cisco Gigabit Switch Routers (GSR) with Fast Ethernet / Gigabit Ethernet cards, from IOS versions 11.2(15)GS1A up to 11.2(19)GS0.2 and some versions of 12.0, do not properly handle line card failures, which allows remote attackers to bypass ACLs or force the interface to stop forwarding packets.

CBOS 2.4.1 and earlier in Cisco 600 routers allows remote attackers to cause a denial of service via a slow stream of TCP SYN packets.

The HTTP server in Cisco IOS 12.0 through 12.1 allows local users to cause a denial of service (crash and reload) via a URL containing a "?/" string.

The cat6000-dot1x component in Cisco IOS 12.2 before 12.2(33)SXI7 does not properly handle (1) a loop between a dot1x enabled port and an open-authentication dot1x enabled port and (2) a loop between a dot1x enabled port and a non-dot1x port, which allows remote attackers to cause a denial of service (traffic storm) via unspecified vectors that trigger many Spanning Tree Protocol (STP) Bridge Protocol Data Unit (BPDU) frames, aka Bug ID CSCtq36327.

Buffer overflow in Cisco TACACS+ tac_plus server allows remote attackers to cause a denial of service via a malformed packet with a long length field.

The Cisco IronPort Email Security Appliance (ESA) allows remote attackers to cause a denial of service (CPU consumption) via long Subject headers in e-mail messages, aka Bug ID CSCzv93864.

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.

Denial of service in Cisco IOS web server allows attackers to reboot the router using a long URL.

Buffer overflow in Cisco 7xx routers through the telnet service.

Denial of service in Cisco routers running NAT via a PORT command from an FTP client to a Telnet port.

Vulnerability in Cisco 7xx series routers allows a remote attacker to cause a system reload via a TCP connection to the router's TELNET port.

Cisco Catalyst LAN switches running Catalyst 5000 supervisor software allows remote attackers to perform a denial of service by forcing the supervisor module to reload.

Unspecified vulnerability in Cisco ASA 5500 Series Adaptive Security Appliance 7.0 before 7.0(8.10), 7.2 before 7.2(4.45), 8.0 before 8.0(5.1), 8.1 before 8.1(2.37), and 8.2 before 8.2(1.15); and Cisco PIX 500 Series Security Appliance; allows remote attackers to cause a denial of service (active IPsec tunnel loss and prevention of new tunnels) via a malformed IKE message through an existing tunnel to UDP port 4500, aka Bug ID CSCtc47782.

Cisco PIX firewall and CBAC IP fragmentation attack results in a denial of service.

Cisco TFTP Server 1.1 allows remote attackers to cause a denial of service (daemon crash) via a crafted (1) read (aka RRQ) or (2) write (aka WRQ) request, or other TFTP packet. NOTE: some of these details are obtained from third party information.

The web-based management interface on Cisco Small Business 220 devices with firmware before 1.0.1.1 allows remote attackers to cause a denial of service (interface outage) via a crafted HTTP request, aka Bug ID CSCuz76238.

Cisco Adaptive Security Appliances (ASA) 5500 series devices with software before 8.2(3) allow remote attackers to cause a denial of service (ASDM syslog outage) via a long URL, aka Bug IDs CSCsm11264 and CSCtb92911.

The proxy process on Cisco Web Security Appliance (WSA) devices through 9.1.0-070 allows remote attackers to cause a denial of service (CPU consumption) by establishing an FTP session and then improperly terminating the control connection after a file transfer, aka Bug ID CSCuy43468.

Memory leak in the gk_circuit_info_do_in_acf function in the H.323 implementation in Cisco IOS before 15.0(1)XA allows remote attackers to cause a denial of service (memory consumption) via a large number of calls over a long duration, as demonstrated by InterZone Clear Token (IZCT) test traffic, aka Bug ID CSCsz72535.

A vulnerability in the web application for Cisco IP Phones could allow an unauthenticated, remote attacker to execute code with root privileges or cause a reload of an affected IP phone, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software fails to check the bounds of input data. An attacker could exploit this vulnerability by sending a crafted HTTP request to the web server of a targeted device. A successful exploit could allow the attacker to remotely execute code with root privileges or cause a reload of an affected IP phone, resulting in a DoS condition.

The General Packet Radio Switching Tunneling Protocol 1 (aka GTPv1) implementation on Cisco ASR 5000 Packet Data Network Gateway devices before 19.4 allows remote attackers to cause a denial of service (Session Manager process restart) via a crafted GTPv1 packet, aka Bug ID CSCuz46198.

Cisco IOS XR 6.0 and 6.0.1 on NCS 6000 devices allows remote attackers to cause a denial of service (OSPFv3 process reload) via crafted OSPFv3 packets, aka Bug ID CSCuz66289.

The REST interface in Cisco Spark 2015-06 allows remote attackers to cause a denial of service (resource outage) by accessing an administrative page, aka Bug ID CSCuv84125.

libclamav in ClamAV (aka Clam AntiVirus), as used in Advanced Malware Protection (AMP) on Cisco Email Security Appliance (ESA) devices before 9.7.0-125 and Web Security Appliance (WSA) devices before 9.0.1-135 and 9.1.x before 9.1.1-041, allows remote attackers to cause a denial of service (AMP process restart) via a crafted document, aka Bug IDs CSCuv78533 and CSCuw60503.

Attackers can crash a Cisco IOS router or device, provided they can get to an interactive prompt (such as a login). This applies to some IOS 9.x, 10.x, and 11.x releases.

The Neighbor Discovery (ND) protocol implementation in the IPv6 stack in Cisco IOS XE 2.1 through 3.17S, IOS XR 2.0.0 through 5.3.2, and NX-OS allows remote attackers to cause a denial of service (packet-processing outage) via crafted ND messages, aka Bug ID CSCuz66542, as exploited in the wild in May 2016.

emWEB on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software before 8.2(3) allows remote attackers to cause a denial of service (daemon crash) via a request for a document whose name contains space characters, aka Bug ID CSCsy08416.

The HTTPS Proxy feature in Cisco AsyncOS before 8.5.3-051 and 9.x before 9.0.0-485 on Web Security Appliance (WSA) devices allows remote attackers to cause a denial of service (service outage) by leveraging certain intranet connectivity and sending a malformed HTTPS request, aka Bug ID CSCuu24840.

Cisco TelePresence Video Communications Server (VCS) X8.x before X8.7.2 allows remote attackers to cause a denial of service (service disruption) via a crafted URI in a SIP header, aka Bug ID CSCuy43258.

Cisco Prime Network Analysis Module (NAM) before 6.2(1-b) miscalculates IPv6 payload lengths, which allows remote attackers to cause a denial of service (mond process crash and monitoring outage) via crafted IPv6 packets, aka Bug ID CSCuy37324.

The TCP implementation in Cisco Videoscape Distribution Suite for Internet Streaming (VDS-IS) 3.3(0), 3.3(1), 4.0(0), and 4.1(0) does not properly initiate new TCP sessions when a previous session is in a FIN wait state, which allows remote attackers to cause a denial of service (TCP outage) via vectors involving FIN packets, aka Bug ID CSCuy45136.

The web-management GUI implementation on Cisco Small Business SG300 devices 1.4.1.x allows remote attackers to cause a denial of service (HTTPS outage) via crafted HTTPS requests, aka Bug ID CSCuw87174.

Cisco IOS XR through 5.3.2 mishandles Local Packet Transport Services (LPTS) flow-base entries, which allows remote attackers to cause a denial of service (session drop) by making many connection attempts to open TCP ports, aka Bug ID CSCux95576.

The packet-processing microcode in Cisco IOS 15.2(2)EA, 15.2(2)EA1, 15.2(2)EA2, and 15.2(4)EA on Industrial Ethernet 4000 devices and 15.2(2)EB and 15.2(2)EB1 on Industrial Ethernet 5000 devices allows remote attackers to cause a denial of service (packet data corruption) via crafted IPv4 ICMP packets, aka Bug ID CSCuy13431.

Cisco IOS XR 4.2.3, 4.3.0, 4.3.4, and 5.3.1 on ASR 9000 devices allows remote attackers to cause a denial of service (CRC and symbol errors, and interface flap) via crafted bit patterns in packets, aka Bug ID CSCuv78548.