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 ingress packet processing function of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource allocation when an affected device processes network traffic in software switching mode (punted). An attacker could exploit this vulnerability by sending specific streams of Layer 2 or Layer 3 protocol data units (PDUs) to an affected device. A successful exploit could cause the affected device to run out of buffer resources, which could make the device unable to process or forward traffic, resulting in a DoS condition. The device would need to be restarted to regain functionality.

The voice-sipstack component in Cisco Unified Communications Manager (CUCM) 8.5 allows remote attackers to cause a denial of service (core dump) via vectors involving SIP messages that arrive after an upgrade, aka Bug ID CSCtj87367.

A vulnerability in the Trust Verification Service (TVS) of Cisco Unified Communications Manager could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of Transport Layer Security (TLS) traffic by the affected software. An attacker could exploit this vulnerability by generating incomplete traffic streams. A successful exploit could allow the attacker to deny access to the TVS for an affected device, resulting in a DoS condition, until an administrator restarts the service. Known Affected Releases 10.0(1.10000.24) 10.5(2.10000.5) 11.0(1.10000.10) 9.1(2.10000.28). Cisco Bug IDs: CSCux21905.

Cisco Sourcefire Snort 3.0 before build 233 mishandles Ether Type Validation. Since valid ether type and IP protocol numbers do not overlap, Snort++ stores all protocol decoders in a single array. That makes it possible to craft packets that have IP protocol numbers in the ether type field which will confuse the Snort++ decoder. For example, an eth:llc:snap:icmp6 packet will cause a crash because there is no ip6 header with which to calculate the icmp6 checksum. Affected decoders include gre, llc, trans_bridge, ciscometadata, linux_sll, and token_ring. The fix adds a check in the packet manager to validate the ether type before indexing the decoder array. An out of range ether type will raise 116:473.

The XML API service in the Fabric Interconnect component in Cisco Unified Computing System (UCS) allows remote attackers to cause a denial of service (API service outage) via a malformed XML document in a packet, aka Bug ID CSCtg48206.

OpenSSL 0.9.6 before 0.9.6d does not properly handle unknown message types, which allows remote attackers to cause a denial of service (infinite loop), as demonstrated using the Codenomicon TLS Test Tool.

The sensor in Cisco Intrusion Prevention System (IPS) 7.0 and 7.1 allows remote attackers to cause a denial of service (file-handle exhaustion and mainApp hang) by making authentication attempts that exceed the configured limit, aka Bug ID CSCto51204.

Cisco Unified Contact Center Express (aka CCX) 8.0 and 8.5 allows remote attackers to cause a denial of service via network traffic, as demonstrated by an SEC-BE-STABLE test case, aka Bug ID CSCth33834.

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.

A vulnerability in the ICMP ingress packet processing of Cisco TelePresence Collaboration Endpoint (CE) Software could allow an unauthenticated, remote attacker to cause the TelePresence endpoint to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to incomplete input validation for the size of a received ICMP packet. An attacker could exploit this vulnerability by sending a crafted ICMP packet to the local IP address of the targeted endpoint. A successful exploit could allow the attacker to cause a DoS of the TelePresence endpoint, during which time calls could be dropped. This vulnerability would affect either IPv4 or IPv6 ICMP traffic. This vulnerability affects the following Cisco TelePresence products when running software release CE8.1.1, CE8.2.0, CE8.2.1, CE8.2.2, CE 8.3.0, or CE8.3.1: Spark Room OS, TelePresence DX Series, TelePresence MX Series, TelePresence SX Quick Set Series, TelePresence SX Series. Cisco Bug IDs: CSCvb95396.

Cisco ONS 15327 before 4.1(3), ONS 15454 before 4.6(1), and ONS 15454 SD before 4.1(3) allows remote attackers to cause a denial of service (reset) by not sending the ACK portion of the TCP three-way handshake and sending an invalid response instead.

The DNS server for Cisco Content Service Switch (CSS) 11000 and 11500, when prompted for a nonexistent AAAA record, responds with response code 3 (NXDOMAIN or "Name Error") instead of response code 0 ("No Error"), which allows remote attackers to cause a denial of service (inaccessible domain) by forcing other DNS servers to send and cache a request for a AAAA record to the vulnerable server.

Cisco VPN 3000 series concentrators and Cisco VPN 3002 Hardware Client 2.x.x through 3.6.7 allows remote attackers to cause a denial of service (reload) via a malformed SSH initialization packet.

Cisco Headend System Release allows remote attackers to cause a denial of service (DHCP and TFTP outage) via a flood of crafted UDP traffic, aka Bug ID CSCus04097.

STCAPP (aka the SCCP telephony control application) on Cisco IOS before 15.0(1)XA1 does not properly handle multiple calls to a shared line, which allows remote attackers to cause a denial of service (port hang) by simultaneously ending two calls that were controlled by CallManager Express (CME), aka Bug ID CSCtd42552.

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 SSL/TLS handshaking code in OpenSSL 0.9.7a, 0.9.7b, and 0.9.7c, when using Kerberos ciphersuites, does not properly check the length of Kerberos tickets during a handshake, which allows remote attackers to cause a denial of service (crash) via a crafted SSL/TLS handshake that causes an out-of-bounds read.

Cisco Firewall Services Module (FWSM) in Cisco Catalyst 6500 and 7600 series devices allows remote attackers to cause a denial of service (crash and reload) via an SNMPv3 message when snmp-server is set.

A vulnerability in the HTTP 2.0 request handling code of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause the Event Management Service daemon (emsd) to crash, resulting in a denial of service (DoS) condition. More Information: CSCvb14425. Known Affected Releases: 6.1.1.BASE. Known Fixed Releases: 6.1.2.6i.MGBL 6.1.22.9i.MGBL 6.2.1.14i.MGBL.

A vulnerability in RADIUS Change of Authorization (CoA) request processing in the Cisco Wireless LAN Controller (WLC) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition by disconnecting a single connection. This vulnerability affects Cisco Wireless LAN Controller running software release 8.3.102.0. More Information: CSCvb01835. Known Fixed Releases: 8.4(1.49) 8.3(111.0) 8.3(108.0) 8.3(104.24) 8.3(102.3).

A vulnerability in TCP port management in Cisco ONS 15454 Series Multiservice Provisioning Platforms could allow an unauthenticated, remote attacker to cause the controller card to unexpectedly reload. More Information: CSCuw26032. Known Affected Releases: 10.51.

Cisco PIX firewall 6.2.x through 6.2.3, when configured as a VPN Client, allows remote attackers to cause a denial of service (dropped IPSec tunnel connection) via an IKE Phase I negotiation request to the outside interface of the firewall.

Buffer overflow in the Cisco Firewall Services Module (FWSM) in Cisco Catalyst 6500 and 7600 series devices allows remote attackers to cause a denial of service (crash and reload) via HTTP auth requests for (1) TACACS+ or (2) RADIUS authentication.

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.

A vulnerability in the Cisco Unified Reporting upload tool accessed via the Cisco Unified Communications Manager could allow an unauthenticated, remote attacker to modify arbitrary files on the file system. More Information: CSCvb61698. Known Affected Releases: 11.5(1.11007.2). Known Fixed Releases: 12.0(0.98000.168) 12.0(0.98000.178) 12.0(0.98000.399) 12.0(0.98000.510) 12.0(0.98000.536) 12.0(0.98500.7).

An IKE Packet Parsing Denial of Service Vulnerability in the ipsecmgr process of Cisco ASR 5000 Software could allow an unauthenticated, remote attacker to cause the ipsecmgr process to reload. More Information: CSCuy06917 CSCuy45036 CSCuy59525. Known Affected Releases: 20.0.0 20.0.M0.62842 20.0.v0 20.0.M0.63229 20.1.0 20.1.a0 20.1.v0 21.0.0 21.0.v0. Known Fixed Releases: 20.0.0 20.0.0.63250 20.0.M0.63148 20.0.R0.63294 20.0.R0.63316 20.0.V0.63170 20.0.VG0.63188 20.0.v0 20.0.v0.64175 20.0.vg0.63522 20.1.A0.63166 20.2.A0.63174 20.1.A0.63232 20.2.A0.63237 20.0.M0.63226 20.0.M0.63229 20.0.R0.63294 20.0.R0.63316 20.0.V0.63263 20.0.VG0.63233 20.0.v0 20.0.v0.64175 20.0.vg0.63522 20.1.0 20.1.0.63959 20.1.M0.63876 20.1.T0.63886 20.1.V0.64231 20.1.VA0.64194 20.1.VB0.64210 20.1.a0 20.1.a0.64023 20.1.v0 20.1.v0.64607 20.2.A0.63895 21.0.0 21.0.0.65256 21.0.M0.63881 21.0.M0.64281 21.0.PP0.64366 21.0.V0.65052 21.0.v0 21.0.v0.65831 21.0.vb0.65887 21.1.R0.65130 21.1.R0.65135.

OpenSSL 0.9.6k allows remote attackers to cause a denial of service (crash via large recursion) via malformed ASN.1 sequences.

Cisco IOS XR 3.4.0 through 3.9.1, when BGP is enabled, does not properly handle unrecognized transitive attributes, which allows remote attackers to cause a denial of service (peering reset) via a crafted prefix announcement, as demonstrated in the wild in August 2010 with attribute type code 99, aka Bug ID CSCti62211.

A vulnerability in Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, remote attacker to cause a queue wedge on a leaf switch, which could result in critical control plane traffic to the device being dropped. This could result in one or more leaf switches being removed from the fabric. This vulnerability is due to mishandling of ingress TCP traffic to a specific port. An attacker could exploit this vulnerability by sending a stream of TCP packets to a specific port on a Switched Virtual Interface (SVI) configured on the device. A successful exploit could allow the attacker to cause a specific packet queue to queue network buffers but never process them, leading to an eventual queue wedge. This could cause control plane traffic to be dropped, resulting in a denial of service (DoS) condition where the leaf switches are unavailable. Note: This vulnerability requires a manual intervention to power-cycle the device to recover.

A vulnerability in the DNS application layer gateway (ALG) functionality used by Network Address Translation (NAT) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a logic error that occurs when an affected device inspects certain DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through an affected device that is performing NAT for DNS packets. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability can be exploited only by traffic that is sent through an affected device via IPv4 packets. The vulnerability cannot be exploited via IPv6 traffic.

Cisco IOS XR 5.2.2 allows remote attackers to cause a denial of service (process restart) via a crafted OSPF Link State Advertisement (LSA) update, aka Bug ID CSCvb05643.

A vulnerability in IPv6 packet fragment reassembly of StarOS for Cisco Aggregation Services Router (ASR) 5000 Series Switch could allow an unauthenticated, remote attacker to cause an unexpected reload of the Network Processing Unit (NPU) process. More Information: CSCva84552. Known Affected Releases: 20.0.0 21.0.0 21.0.M0.64702. Known Fixed Releases: 21.0.0 21.0.0.65256 21.0.M0.64970 21.0.V0.65150 21.1.A0.64973 21.1.PP0.65270 21.1.R0.65130 21.1.R0.65135 21.1.VC0.65203.

A vulnerability in the Slowpath of StarOS for Cisco ASR 5500 Series routers with Data Processing Card 2 (DPC2) could allow an unauthenticated, remote attacker to cause a subset of the subscriber sessions to be disconnected, resulting in a partial denial of service (DoS) condition. This vulnerability affects Cisco ASR 5500 devices with Data Processing Card 2 (DPC2) running StarOS 18.0 or later. More Information: CSCvb12081. Known Affected Releases: 18.7.4 19.5.0 20.0.2.64048 20.2.3 21.0.0. Known Fixed Releases: 18.7.4 18.7.4.65030 18.8.M0.65044 19.5.0 19.5.0.65092 19.5.M0.65023 19.5.M0.65050 20.2.3 20.2.3.64982 20.2.3.65017 20.2.a4.65307 20.3.M0.64984 20.3.M0.65029 20.3.M0.65037 20.3.M0.65071 20.3.T0.64985 20.3.T0.65031 20.3.T0.65043 20.3.T0.65067 21.0.0 21.0.0.65256 21.0.M0.64922 21.0.M0.64983 21.0.M0.65140 21.0.V0.65150 21.1.A0.64932 21.1.A0.64987 21.1.A0.65145 21.1.PP0.65270 21.1.R0.65130 21.1.R0.65135 21.1.R0.65154 21.1.VC0.65203 21.2.A0.65147.

A vulnerability in HTTP URL parsing of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) vulnerability due to the proxy process unexpectedly restarting. More Information: CSCvb04312. Known Affected Releases: 9.0.1-162 9.1.1-074. Known Fixed Releases: 10.1.0-129 9.1.2-010.

A vulnerability in the IPsec component of StarOS for Cisco ASR 5000 Series routers could allow an unauthenticated, remote attacker to terminate all active IPsec VPN tunnels and prevent new tunnels from establishing, resulting in a denial of service (DoS) condition. This vulnerability affects the following Cisco products: Cisco ASR 5000/5500 Series routers, Cisco Virtualized Packet Core (VPC). More Information: CSCva13631. Known Affected Releases: 20.0.0 20.1.0 20.2.0 20.2.3 20.2.v1 21.0.0 21.0.M0.64246. Known Fixed Releases: 20.2.3 20.2.3.65026 20.2.a4.65307 20.2.v1 20.2.v1.65353 20.3.M0.65037 20.3.T0.65043 21.0.0 21.0.0.65256 21.0.M0.64595 21.0.M0.64860 21.0.M0.65140 21.0.V0.65052 21.0.V0.65150 21.0.V0.65366 21.0.VC0.64639 21.1.A0.64861 21.1.A0.65145 21.1.PP0.65270 21.1.R0.65130 21.1.R0.65135 21.1.R0.65154 21.1.VC0.64898 21.1.VC0.65203 21.2.A0.65147.

A vulnerability in Advanced Malware Protection (AMP) for Cisco Email Security Appliances (ESA) and Web Security Appliances (WSA) could allow an unauthenticated, remote attacker to cause a partial denial of service (DoS) condition due to the AMP process unexpectedly restarting. Affected Products: Cisco AsyncOS Software for Email Security Appliances (ESA) versions 9.5 and later up to the first fixed release, Cisco AsyncOS Software for Web Security Appliances (WSA) all versions prior to the first fixed release. More Information: CSCux56406, CSCux59928. Known Affected Releases: 9.6.0-051 9.7.0-125 8.8.0-085 9.5.0-444 WSA10.0.0-000. Known Fixed Releases: 9.7.1-066 WSA10.0.0-233.

Cisco VPN 3000 series concentrators and Cisco VPN 3002 Hardware Client 2.x.x through 3.6.7A allow remote attackers to cause a denial of service (slowdown and possibly reload) via a flood of malformed ICMP packets.

The web server for Cisco Aironet AP1x00 Series Wireless devices running certain versions of IOS 12.2 allow remote attackers to cause a denial of service (reload) via a malformed URL.

Cisco CSS 11000 routers on the CS800 chassis allow remote attackers to cause a denial of service (CPU consumption or reboot) via a large number of TCP SYN packets to the circuit IP address, aka "ONDM Ping failure."

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.

A vulnerability in the internal packet-processing functionality of Cisco Firepower Threat Defense (FTD) Software for the Cisco Firepower 2100 Series could allow an unauthenticated, remote attacker to cause an affected device to stop processing traffic, resulting in a denial of service (DoS) condition. The vulnerability is due to a logic error, which may prevent ingress buffers from being replenished under specific traffic conditions. An attacker could exploit this vulnerability by sending a series of crafted packets to an affected device. A successful exploit could allow the attacker to consume all input buffers, which are shared between all interfaces, leading to a queue wedge condition in all active interfaces. This situation would cause an affected device to stop processing any incoming traffic and result in a DoS condition until the device is reloaded manually.

A vulnerability in the web-based management interface of the Cisco RV110W Wireless-N VPN Firewall, Cisco RV130W Wireless-N Multifunction VPN Router, and Cisco RV215W Wireless-N VPN Router could allow an unauthenticated, remote attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of user-supplied data in the web-based management interface. An attacker could exploit this vulnerability by sending malicious HTTP requests to a targeted device. A successful exploit could allow the attacker to reload the device and causing a DoS condition.

The igmp_snoop_orib_fill_source_update function in the IGMP process in NX-OS 5.0 and 5.1 on Cisco Nexus 5000 series switches allows remote attackers to cause a denial of service (device reload) via IGMP packets, aka Bug ID CSCts46521.

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 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.

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.

A vulnerability in the web proxy functionality of Cisco AsyncOS Software for Cisco Web Security Appliance 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 HTTP and HTTPS requests. An attacker could exploit this vulnerability by sending a malformed HTTP or HTTPS request to an affected device. An exploit could allow the attacker to cause a restart of the web proxy process, resulting in a temporary DoS condition.

The MallocLite implementation in Cisco IOS 12.0, 12.2, 15.0, 15.1, and 15.2 allows remote attackers to cause a denial of service (Route Processor crash) via a BGP UPDATE message with a modified local-preference (aka LOCAL_PREF) attribute length, aka Bug ID CSCtq06538.