A vulnerability in the TCP socket code of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a state condition between the socket state and the transmission control block (TCB) state. While this vulnerability potentially affects all TCP applications, the only affected application observed so far is the HTTP server. An attacker could exploit this vulnerability by sending specific HTTP requests at a sustained rate to a reachable IP address of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device.

A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of 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 insufficient error handling in DNS name resolution by the affected software. An attacker could exploit this vulnerability by sending specially formatted email messages that are processed by an affected device. A successful exploit could allow the attacker to cause the device to become unreachable from management interfaces or to process additional email messages for a period of time until the device recovers, resulting in a DoS condition. Continued attacks could cause the device to become completely unavailable, resulting in a persistent DoS condition.

A vulnerability in the Forwarding Information Base (FIB) code of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, network attacker to cause a denial of service (DoS) condition. The vulnerability is due to a limitation in the way the FIB is internally representing recursive routes. An attacker could exploit this vulnerability by injecting routes into the routing protocol that have a specific recursive pattern. The attacker must be in a position on the network that provides the ability to inject a number of recursive routes with a specific pattern. An exploit could allow the attacker to cause an affected device to reload, creating a DoS condition. Cisco Bug IDs: CSCva91655.

A vulnerability in the Network Address Translation (NAT) Session Initiation Protocol (SIP) Application Layer Gateway (ALG) of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper processing of SIP packets in transit while NAT is performed on an affected device. An unauthenticated, remote attacker could exploit this vulnerability by sending crafted SIP packets via UDP port 5060 through an affected device that is performing NAT for SIP packets. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the web user interface of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a double-free-in-memory handling by the affected software when specific HTTP requests are processed. An attacker could exploit this vulnerability by sending specific HTTP requests to the web user interface of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device. To exploit this vulnerability, the attacker must have access to the management interface of the affected software, which is typically connected to a restricted management network.

Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices that are running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later. Cisco Bug IDs: CSCuy32360, CSCuz60599.

A vulnerability in Cisco AMP for Endpoints Mac Connector Software installed on Apple macOS 10.12 could allow an unauthenticated, remote attacker to cause a kernel panic on an affected system, resulting in a denial of service (DoS) condition. The vulnerability exists if the affected software is running in Block network conviction mode. Exploitation could occur if the system that is running the affected software starts a server process and an address in the IP blacklist cache of the affected software attempts to connect to the affected system. A successful exploit could allow the attacker to cause a kernel panic on the system that is running the affected software, resulting in a DoS condition. Cisco Bug IDs: CSCvk08192.

Cisco Adaptive Security Appliance (ASA) software 7.2 and 8.2 before 8.2(5.58), 8.3 and 8.4 before 8.4(7.29), 8.5 through 8.7 before 8.7(1.17), 9.0 before 9.0(4.37), 9.1 before 9.1(6.4), 9.2 before 9.2(4), 9.3 before 9.3(3.1), and 9.4 before 9.4(1.1) allows remote attackers to cause a denial of service (device reload) via a crafted DNS response, aka Bug ID CSCut03495.

The DHCPv6 relay implementation in Cisco Adaptive Security Appliance (ASA) software 9.0 before 9.0(4.37), 9.1 before 9.1(6.6), 9.2 before 9.2(4), 9.3 before 9.3(3.5), and 9.4 before 9.4(2) allows remote attackers to cause a denial of service (device reload) via crafted DHCPv6 packets, aka Bug IDs CSCus56252 and CSCus57142.

Cisco Unified Computing System (UCS) 2.2(3f)A on Fabric Interconnect 6200 devices allows remote attackers to cause a denial of service (CPU consumption or device outage) via a SYN flood on the SSH port during the booting process, aka Bug ID CSCuu81757.

Race condition in the IPv6-to-IPv4 functionality in Cisco IOS 15.3S in the Performance Routing Engine (PRE) module on UBR devices allows remote attackers to cause a denial of service (NULL pointer free and module crash) by triggering intermittent connectivity with many IPv6 CPE devices, aka Bug ID CSCug47366.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU6, 8.6 before 8.6(2a)SU4, and 9.x before 9.1(2)SU2, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (SIP outage) via a crafted UDP packet, aka Bug ID CSCuh25062.

Cisco IOS XR 5.0.1 and 5.2.1 on Network Convergence System (NCS) 6000 devices and 5.1.3 and 5.1.4 on Carrier Routing System X (CRS-X) devices allows remote attackers to cause a denial of service (line-card reload) via malformed IPv6 packets with extension headers, aka Bug ID CSCuq95241.

Cisco IOS XE 3.10.2S on an ASR 1000 device with an Embedded Services Processor (ESP) module, when NAT is enabled, allows remote attackers to cause a denial of service (module crash) via malformed H.323 packets, aka Bug ID CSCup21070.

Race condition in the TLS implementation in MainApp in the management interface in Cisco Intrusion Prevention System (IPS) Software before 7.3(3)E4 allows remote attackers to cause a denial of service (process hang) by establishing many HTTPS sessions, aka Bug ID CSCuq40652.

The TFTP server in Cisco IOS 12.2(44)SQ1, 12.2(33)XN1, 12.4(25e)JAM1, 12.4(25e)JAO5m, 12.4(23)JY, 15.0(2)ED1, 15.0(2)EY3, 15.1(3)SVF4a, and 15.2(2)JB1 and IOS XE 2.5.x, 2.6.x, 3.1.xS, 3.2.xS, 3.3.xS, 3.4.xS, and 3.5.xS before 3.6.0S; 3.1.xSG, 3.2.xSG, and 3.3.xSG before 3.4.0SG; 3.2.xSE before 3.3.0SE; 3.2.xXO before 3.3.0XO; 3.2.xSQ; 3.3.xSQ; and 3.4.xSQ allows remote attackers to cause a denial of service (device hang or reload) via multiple requests that trigger improper memory management, aka Bug ID CSCts66733.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, and 9.x before 9.1(2)SU2, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (core dump and restart) by improperly terminating SIP TCP connections, aka Bug ID CSCul69819.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, 9.x before 9.1(2)SU2, and 10.0 before 10.0(1)SU1, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (core dump and restart) via crafted SIP INVITE messages, aka Bug ID CSCul26267.

Race condition in the Measurement, Aggregation, and Correlation Engine (MACE) implementation in Cisco IOS 15.4(2)T3 and earlier allows remote attackers to cause a denial of service (device reload) via crafted network traffic that triggers improper handling of the timing of process switching and Cisco Express Forwarding (CEF) switching, aka Bug ID CSCul48736.

The call-handling implementation in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, 9.x before 9.1(2)SU2, and 10.0 before 10.0(1)SU1, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (port consumption) by improperly terminating SIP sessions, aka Bug ID CSCul28089.

Race condition in the SSL implementation on Cisco Intrusion Prevention System (IPS) devices allows remote attackers to cause a denial of service by making many management-interface HTTPS connections during the key-regeneration phase of an upgrade, aka Bug ID CSCui25688.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, 9.x before 9.1(2)SU2, and 10.0 before 10.0(1)SU1, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (core dump and restart) via crafted SIP INVITE messages, aka Bug ID CSCul20444.

Race condition in the Common Classification Engine (CCE) in the Measurement, Aggregation, and Correlation Engine (MACE) implementation in Cisco IOS 15.4(2)T3 and earlier allows remote attackers to cause a denial of service (device reload) via crafted network traffic that triggers improper handling of the timing of process switching and Cisco Express Forwarding (CEF) switching, aka Bug ID CSCuj96752.

Cisco IOS on Aironet access points, when "dot11 aaa authenticator" debugging is enabled, allows remote attackers to cause a denial of service via a malformed EAP packet, aka Bug ID CSCul15509.

The SIP IX implementation in Cisco TelePresence Video Communication Server (VCS) and Expressway Software before X8.1.1 allows remote attackers to cause a denial of service (device reload) via crafted SDP packets, aka Bug ID CSCuo42252.

The ALG module in Cisco IOS 15.0 through 15.4 does not properly implement SIP over NAT, which allows remote attackers to cause a denial of service (device reload) via multipart SDP IPv4 traffic, aka Bug ID CSCun54071.

Race condition in the IP logging feature in Cisco Intrusion Prevention System (IPS) Software 7.1(7)E4 and earlier allows remote attackers to cause a denial of service (device reload) via crafted IP traffic that matches a problematic rule, aka Bug ID CSCud82085.

Cisco TelePresence Video Communication Server (VCS) and Expressway Software before X8.1.1 allow remote attackers to cause a denial of service (device reload) via crafted SIP packets, aka Bug IDs CSCum60442 and CSCum60447.

Cisco IOS XR 4.3(.2) and earlier, as used in Cisco Carrier Routing System (CRS), allows remote attackers to cause a denial of service (CPU consumption and IPv6 packet drops) via a malformed IPv6 packet, aka Bug ID CSCuo95165.

Cisco IOS XR 4.1.2 through 5.1.1 on ASR 9000 devices, when a Trident-based line card is used, allows remote attackers to cause a denial of service (NP chip and line card reload) via malformed IPv6 packets, aka Bug ID CSCun71928.

Cisco IOS 15.1(2)SY3 and earlier, when used with Supervisor Engine 2T (aka Sup2T) on Catalyst 6500 devices, allows remote attackers to cause a denial of service (device crash) via crafted multicast packets, aka Bug ID CSCuf60783.

Race condition in the cut-through proxy feature in Cisco Firewall Services Module (FWSM) Software 3.x before 3.2(28) and 4.x before 4.1(15) allows remote attackers to cause a denial of service (device reload) via certain matching traffic, aka Bug ID CSCuj16824.

The multicast listener discovery (MLD) service on Cisco Wireless LAN Controller (WLC) devices 7.2, 7.3, 7.4 before 7.4.121.0, and 7.5, when MLDv2 Snooping is enabled, allows remote attackers to cause a denial of service (device restart) via a malformed IPv6 MLDv2 packet, aka Bug ID CSCuh74233.

Cisco IOS XE does not properly manage memory for TFTP UDP flows, which allows remote attackers to cause a denial of service (memory consumption) via TFTP (1) client or (2) server traffic, aka Bug IDs CSCuh09324 and CSCty42686.

A vulnerability in the FTP inspection engine of Cisco 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 vulnerability exists because the affected software fails to release spinlocks when a device is running low on system memory, if the software is configured to apply FTP inspection and an access control rule to transit traffic, and the access control rule is associated with an FTP file policy. An attacker could exploit this vulnerability by sending a high rate of transit traffic through an affected device to cause a low-memory condition on the device. A successful exploit could allow the attacker to cause a software panic on the affected device, which could cause the device to reload and result in a temporary DoS condition.

A vulnerability in the TCP syslog module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust the 1550-byte buffers on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing boundary check in an internal function. An attacker could exploit this vulnerability by establishing a man-in-the-middle position between an affected device and its configured TCP syslog server and then maliciously modifying the TCP header in segments that are sent from the syslog server to the affected device. A successful exploit could allow the attacker to exhaust buffer on the affected device and cause all TCP-based features to stop functioning, resulting in a DoS condition. The affected TCP-based features include AnyConnect SSL VPN, clientless SSL VPN, and management connections such as Secure Shell (SSH), Telnet, and HTTPS.

The Location Bandwidth Manager (LBM) Intracluster-communication feature in Cisco Unified Communications Manager (CUCM) 9.x before 9.1(1) does not require authentication from the remote LBM Hub node, which allows remote attackers to conduct cache-poisoning attacks against transaction records, and cause a denial of service (bandwidth-pool consumption and call outage), via unspecified vectors, aka Bug ID CSCub28920.

Unspecified vulnerability in the VLAN Trunking Protocol (VTP) implementation on Cisco IOS and CatOS, when the VTP operating mode is not transparent, allows remote attackers to cause a denial of service (device reload or hang) via a crafted VTP packet sent to a switch interface configured as a trunk port.

Cisco Unity 4.x before 4.2(1)ES161, 5.x before 5.0(1)ES53, and 7.x before 7.0(2)ES8, when using anonymous authentication (aka native Unity authentication), allows remote attackers to cause a denial of service (session exhaustion) via a large number of connections.

Unspecified vulnerability in the Multi Protocol Label Switching (MPLS) Forwarding Infrastructure (MFI) in Cisco IOS 12.2 and 12.4 allows remote attackers to cause a denial of service (memory corruption) via crafted packets for which the software path is used.

Cisco IOS 12.4, when IOS firewall Application Inspection Control (AIC) with HTTP Deep Packet Inspection is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed HTTP transit packet.

Unspecified vulnerability in the Session Initiation Protocol (SIP) implementation in Cisco IOS 12.2 through 12.4, when VoIP is configured, allows remote attackers to cause a denial of service (device reload) via unspecified valid SIP messages, aka Cisco bug ID CSCsk42759, a different vulnerability than CVE-2008-3800 and CVE-2008-3801.

Unspecified vulnerability in the Session Initiation Protocol (SIP) implementation in Cisco IOS 12.2 through 12.4 and Unified Communications Manager 4.1 through 6.1, when VoIP is configured, allows remote attackers to cause a denial of service (device or process reload) via unspecified valid SIP messages, aka Cisco Bug ID CSCsu38644, a different vulnerability than CVE-2008-3801 and CVE-2008-3802.

The TCP implementation in (1) Linux, (2) platforms based on BSD Unix, (3) Microsoft Windows, (4) Cisco products, and probably other operating systems allows remote attackers to cause a denial of service (connection queue exhaustion) via multiple vectors that manipulate information in the TCP state table, as demonstrated by sockstress.

Unspecified vulnerability in the Session Initiation Protocol (SIP) implementation in Cisco IOS 12.2 through 12.4 and Unified Communications Manager 4.1 through 6.1, when VoIP is configured, allows remote attackers to cause a denial of service (device or process reload) via unspecified valid SIP messages, aka Cisco Bug ID CSCsm46064, a different vulnerability than CVE-2008-3800 and CVE-2008-3802.

A vulnerability in the SSL/TLS inspection of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series firewalls could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation for certain fields of specific SSL/TLS messages. An attacker could exploit this vulnerability by sending a malformed SSL/TLS message through an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. No manual intervention is needed to recover the device after it has reloaded.