The Certificate Authority Proxy Function (CAPF) service in Cisco Unified Communications Manager 5.x before 5.1(3e) and 6.x before 6.1(3) allows remote attackers to cause a denial of service (voice service outage) by sending malformed input over a TCP session in which the "client terminates prematurely."

A vulnerability in the implementation of the system login block-for command for Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a login process to unexpectedly restart, causing a denial of service (DoS) condition. This vulnerability is due to a logic error in the implementation of the system login block-for command when an attack is detected and acted upon. An attacker could exploit this vulnerability by performing a brute-force login attack on an affected device. A successful exploit could allow the attacker to cause a login process to reload, which could result in a delay during authentication to the affected device.

The BGP Router process in Cisco IOS before 12.2(50)SY1 allows remote attackers to cause a denial of service (memory consumption) via vectors involving BGP path attributes, aka Bug ID CSCsw63003.

The BGP implementation in Cisco NX-OS does not properly filter segment types in AS paths, which allows remote attackers to cause a denial of service (BGP service reset) via a malformed UPDATE message, aka Bug ID CSCtn13043.

A memory leak vulnerability exists in Cisco IOS before 15.2(1)T due to a memory leak in the HTTP PROXY Server process (aka CSCtu52820), when configured with Cisco ISR Web Security with Cisco ScanSafe and User Authenticaiton NTLM configured.

Cisco IOS 11.1(x) through 11.3(x) and 12.0(x) through 12.2(x), when configured for BGP routing, allows remote attackers to cause a denial of service (device reload) via malformed BGP (1) OPEN or (2) UPDATE messages.

A vulnerability in Session Initiation Protocol (SIP) call handling of Cisco IP Phone 8800 Series devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to the SIP process unexpectedly restarting. All active phone calls are dropped as the SIP process restarts. More Information: CSCvc29353. Known Affected Releases: 11.0(0.1). Known Fixed Releases: 11.0(0)MP2.153 11.0(0)MP2.62.

A vulnerability in the Common Open Policy Service (COPS) of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause resource exhaustion, resulting in a denial of service (DoS) condition. This vulnerability is due to a deadlock condition in the code when processing COPS packets under certain conditions. An attacker could exploit this vulnerability by sending COPS packets with high burst rates to an affected device. A successful exploit could allow the attacker to cause the CPU to consume excessive resources, which prevents other control plane processes from obtaining resources and results in a DoS.

A vulnerability in the VXLAN Operation, Administration, and Maintenance (OAM) feature of Cisco NX-OS Software, known as NGOAM, 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 specific packets with a Transparent Interconnection of Lots of Links (TRILL) OAM EtherType. An attacker could exploit this vulnerability by sending crafted packets, including the TRILL OAM EtherType of 0x8902, to a device that is part of a VXLAN Ethernet VPN (EVPN) fabric. A successful exploit could allow the attacker to cause an affected device to experience high CPU usage and consume excessive system resources, which may result in overall control plane instability and cause the affected device to reload. Note: The NGOAM feature is disabled by default.

A vulnerability in the network stack 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 exists because the software improperly releases resources when it processes certain IPv6 packets that are destined to an affected device. An attacker could exploit this vulnerability by sending multiple crafted IPv6 packets to an affected device. A successful exploit could cause the network stack to run out of available buffers, impairing operations of control plane and management plane protocols and resulting in a DoS condition. Manual intervention would be required to restore normal operations on the affected device. For more information about the impact of this vulnerability, see the Details section of this advisory.

A vulnerability in the Border Gateway Protocol (BGP) additional paths feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent authorized users from monitoring the BGP status and cause the BGP process to stop processing new updates, resulting in a denial of service (DOS) condition. The vulnerability is due to an incorrect calculation of lexicographical order when displaying additional path information within Cisco IOS XR Software, which causes an infinite loop. An attacker could exploit this vulnerability by sending a specific BGP update from a BGP neighbor peer session of an affected device; an authorized user must then issue a show bgp command for the vulnerability to be exploited. A successful exploit could allow the attacker to prevent authorized users from properly monitoring the BGP status and prevent BGP from processing new updates, resulting in outdated information in the routing and forwarding tables.

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 Internet Key Exchange Version 1 (IKEv1) XAUTH code of Cisco ASA Software could allow an authenticated, remote attacker to cause a reload of an affected system. The vulnerability is due to insufficient validation of the IKEv1 XAUTH parameters passed during an IKEv1 negotiation. An attacker could exploit this vulnerability by sending crafted parameters. Note: Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability only affects systems configured in routed firewall mode and in single or multiple context mode. This vulnerability can be triggered by IPv4 or IPv6 traffic. A valid IKEv1 Phase 1 needs to be established to exploit this vulnerability, which means that an attacker would need to have knowledge of a pre-shared key or have a valid certificate for phase 1 authentication. This vulnerability affects Cisco ASA Software running on the following products: Cisco ASA 1000V Cloud Firewall, Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Cisco Adaptive Security Virtual Appliance (ASAv), Cisco ASA for Firepower 9300 Series, Cisco ISA 3000 Industrial Security Appliance. Fixed versions: 9.1(7.7) 9.2(4.11) 9.4(4) 9.5(3) 9.6(1.5). Cisco Bug IDs: CSCuz11685.

A vulnerability in the TCP throttling process for the GUI of the Cisco Identity Services Engine (ISE) 2.1(0.474) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device where the ISE GUI may fail to respond to new or established connection requests. The vulnerability is due to insufficient TCP rate limiting protection on the GUI. An attacker could exploit this vulnerability by sending the affected device a high rate of TCP connections to the GUI. An exploit could allow the attacker to cause the GUI to stop responding while the high rate of connections is in progress. Cisco Bug IDs: CSCvc81803.

A vulnerability in the DNS code of Cisco ASA Software could allow an unauthenticated, remote attacker to cause an affected device to reload or corrupt the information present in the device's local DNS cache. The vulnerability is due to a flaw in handling crafted DNS response messages. An attacker could exploit this vulnerability by triggering a DNS request from the Cisco ASA Software and replying with a crafted response. A successful exploit could cause the device to reload, resulting in a denial of service (DoS) condition or corruption of the local DNS cache information. Note: Only traffic directed to the affected device can be used to exploit this vulnerability. This vulnerability affects Cisco ASA Software configured in routed or transparent firewall mode and single or multiple context mode. This vulnerability can be triggered by IPv4 and IPv6 traffic. This vulnerability affects Cisco ASA Software running on the following products: Cisco ASA 1000V Cloud Firewall, Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Cisco Adaptive Security Virtual Appliance (ASAv), Cisco Firepower 9300 ASA Security Module, Cisco ISA 3000 Industrial Security Appliance. Fixed versions: 9.1(7.12) 9.2(4.18) 9.4(3.12) 9.5(3.2) 9.6(2.2). Cisco Bug IDs: CSCvb40898.

A vulnerability in the Session Initiation Protocol (SIP) implementation of Cisco IP Phone 8851 11.0(0.1) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to an abnormal SIP message. An attacker could exploit this vulnerability by manipulating the CANCEL packet. An exploit could allow the attacker to cause a disruption of service to the phone. Cisco Bug IDs: CSCvc34795.

Cisco Adaptive Security Appliance (ASA) Software 8.4(.6) and earlier, when using an unsupported configuration with overlapping criteria for filtering and inspection, allows remote attackers to cause a denial of service (traffic loop and device crash) via a packet that triggers multiple matches, aka Bug ID CSCui45606.

A vulnerability in the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) code of Cisco ASA Software could allow an unauthenticated, remote attacker to cause a reload of the affected system. The vulnerability is due to improper parsing of crafted SSL or TLS packets. An attacker could exploit this vulnerability by sending a crafted packet to the affected system. Note: Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability affects systems configured in routed and transparent firewall mode and in single or multiple context mode. This vulnerability can be triggered by IPv4 and IPv6 traffic. A valid SSL or TLS session is needed to exploit this vulnerability. This vulnerability affects Cisco ASA Software running on the following products: Cisco ASA 1000V Cloud Firewall, Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Cisco Adaptive Security Virtual Appliance (ASAv), Cisco Firepower 9300 ASA Security Module, Cisco ISA 3000 Industrial Security Appliance. Fixed versions: 8.4(7.31) 9.0(4.39) 9.1(7) 9.2(4.6) 9.3(3.8) 9.4(2) 9.5(2). Cisco Bug IDs: CSCuv48243.

A vulnerability in the IPsec code of Cisco ASA Software could allow an authenticated, remote attacker to cause a reload of the affected system. The vulnerability is due to improper parsing of malformed IPsec packets. An attacker could exploit this vulnerability by sending malformed IPsec packets to the affected system. Note: Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability affects systems configured in routed firewall mode only and in single or multiple context mode. This vulnerability can be triggered by IPv4 and IPv6 traffic. An attacker needs to establish a valid IPsec tunnel before exploiting this vulnerability. This vulnerability affects Cisco ASA Software running on the following products: Cisco ASA 1000V Cloud Firewall, Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Cisco Adaptive Security Virtual Appliance (ASAv), Cisco Firepower 9300 ASA Security Module, Cisco ISA 3000 Industrial Security Appliance. Fixed versions: 9.1(7.8) 9.2(4.15) 9.4(4) 9.5(3.2) 9.6(2). Cisco Bug IDs: CSCun16158.

A "Cisco Firepower Threat Defense 6.0.0 through 6.2.2 and Cisco ASA with FirePOWER Module Denial of Service" vulnerability in the access control policy of Cisco Firepower System Software could allow an authenticated, remote attacker to cause an affected system to stop inspecting and processing packets, resulting in a denial of service (DoS) condition. The vulnerability is due to improper SSL policy handling by the affected software when packets are passed through the sensing interfaces of an affected system. An attacker could exploit this vulnerability by sending crafted packets through a targeted system. This vulnerability affects Cisco Firepower System Software that is configured with the SSL policy feature. Cisco Bug IDs: CSCvc84361.

A vulnerability in the ingress UDP packet processing functionality of Cisco Virtualized Packet Core-Distributed Instance (VPC-DI) Software 19.2 through 21.0 could allow an unauthenticated, remote attacker to cause both control function (CF) instances on an affected system to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient handling of user-supplied data by the affected software. An attacker could exploit this vulnerability by sending crafted UDP packets to the distributed instance (DI) network addresses of both CF instances on an affected system. A successful exploit could allow the attacker to cause an unhandled error condition on the affected system, which would cause the CF instances to reload and consequently cause the entire VPC to reload, resulting in the disconnection of all subscribers and a DoS condition on the affected system. This vulnerability can be exploited via IPv4 traffic only. Cisco Bug IDs: CSCvc01665 CSCvc35565.

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 Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE 3.16 could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to a race condition that could occur when the affected software processes an SNMP read request that contains certain criteria for a specific object ID (OID) and an active crypto session is disconnected on an affected device. An attacker who can authenticate to an affected device could trigger this vulnerability by issuing an SNMP request for a specific OID on the device. A successful exploit will cause the device to restart due to an attempt to access an invalid memory region. The attacker does not control how or when crypto sessions are disconnected on the device. Cisco Bug IDs: CSCvb94392.

A vulnerability in the TCP throttling process for Cisco IoT Field Network Director (IoT-FND) could allow an unauthenticated, remote attacker to cause the system to consume additional memory, eventually forcing the device to restart, aka Memory Exhaustion. The vulnerability is due to insufficient rate-limiting protection. An attacker could exploit this vulnerability by sending a high rate of TCP packets to a specific group of open listening ports on a targeted device. An exploit could allow the attacker to cause the system to consume additional memory. If enough available memory is consumed, the system will restart, creating a temporary denial of service (DoS) condition. The DoS condition will end after the device has finished the restart process. This vulnerability affects the following Cisco products: Connected Grid Network Management System, if running a software release prior to IoT-FND Release 4.0; IoT Field Network Director, if running a software release prior to IoT-FND Release 4.0. Cisco Bug IDs: CSCvc77164.

A vulnerability in the Session Initiation Protocol (SIP) of the Cisco TelePresence Codec (TC) and Collaboration Endpoint (CE) Software could allow an unauthenticated, remote attacker to cause a TelePresence endpoint to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of flow-control mechanisms within the software. An attacker could exploit this vulnerability by sending a flood of SIP INVITE packets to the affected device. An exploit could allow the attacker to impact the availability of services and data of the device, including a complete DoS condition. This vulnerability affects the following Cisco TC and CE platforms when running software versions prior to TC 7.3.8 and CE 8.3.0. Cisco Bug IDs: CSCux94002.

A vulnerability in the HTTP remote procedure call (RPC) service of set-top box (STB) receivers manufactured by Cisco for Yes could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the firmware of an affected device fails to handle certain XML values that are passed to the HTTP RPC service listening on the local subnet of the device. An attacker could exploit this vulnerability by submitting a malformed request to an affected device. A successful attack could cause the affected device to restart, resulting in a DoS condition. Yes has updated the affected devices with firmware that addresses this vulnerability. Customers are not required to take action. Vulnerable Products: This vulnerability affects YesMaxTotal, YesMax HD, and YesQuattro STB devices. Cisco Bug IDs: CSCvd08812.

A vulnerability in the Layer 2 Tunneling Protocol (L2TP) parsing function of Cisco IOS (12.0 through 12.4 and 15.0 through 15.6) and Cisco IOS XE (3.1 through 3.18) could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to insufficient validation of L2TP packets. An attacker could exploit this vulnerability by sending a crafted L2TP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS or Cisco IOS XE Software if the L2TP feature is enabled for the device and the device is configured as an L2TP Version 2 (L2TPv2) or L2TP Version 3 (L2TPv3) endpoint. By default, the L2TP feature is not enabled. Cisco Bug IDs: CSCuy82078.

Apache Log4j2 2.0-beta9 through 2.15.0 (excluding security releases 2.12.2, 2.12.3, and 2.3.1) JNDI features used in configuration, log messages, and parameters do not protect against attacker controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.15.0, this behavior has been disabled by default. From version 2.16.0 (along with 2.12.2, 2.12.3, and 2.3.1), this functionality has been completely removed. Note that this vulnerability is specific to log4j-core and does not affect log4net, log4cxx, or other Apache Logging Services projects.

A vulnerability in the DHCP client implementation of Cisco IOS (12.2, 12.4, and 15.0 through 15.6) and Cisco IOS XE (3.3 through 3.7) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability occurs during the parsing of a crafted DHCP packet. An attacker could exploit this vulnerability by sending crafted DHCP packets to an affected device that is configured as a DHCP client. A successful exploit could allow the attacker to cause a reload of an affected device, resulting in a DoS condition. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS or IOS XE Software and using a specific DHCP client configuration. Cisco Bug IDs: CSCuu43892.

A vulnerability in the Stream Control Transmission Protocol (SCTP) decoder of the Cisco NetFlow Generation Appliance (NGA) with software before 1.1(1a) could allow an unauthenticated, remote attacker to cause the device to hang or unexpectedly reload, causing a denial of service (DoS) condition. The vulnerability is due to incomplete validation of SCTP packets being monitored on the NGA data ports. An attacker could exploit this vulnerability by sending malformed SCTP packets on a network that is monitored by an NGA data port. SCTP packets addressed to the IP address of the NGA itself will not trigger this vulnerability. An exploit could allow the attacker to cause the appliance to become unresponsive or reload, causing a DoS condition. User interaction could be needed to recover the device using the reboot command from the CLI. The following Cisco NetFlow Generation Appliances are vulnerable: NGA 3140, NGA 3240, NGA 3340. Cisco Bug IDs: CSCvc83320.

A vulnerability in the wireless controller manager of Cisco IOS XE could allow an unauthenticated, adjacent attacker to cause a restart of the switch and result in a denial of service (DoS) condition. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by submitting a crafted association request. An exploit could allow the attacker to cause the switch to restart. This vulnerability affects Cisco Catalyst 3650 and 3850 switches running IOS XE Software versions 16.1 through 16.3.3, and acting as wireless LAN controllers (WLC). Cisco Bug IDs: CSCvd45069.

A vulnerability in SSL/TLS message handler for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because incoming SSL/TLS packets are not properly processed. An attacker could exploit this vulnerability by sending a crafted SSL/TLS packet 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 802.11 Wireless Multimedia Extensions (WME) action frame processing in Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability is due to incomplete input validation of the 802.11 WME packet header. An attacker could exploit this vulnerability by sending malformed 802.11 WME frames to a targeted device. A successful exploit could allow the attacker to cause the WLC to reload unexpectedly. The fixed versions are 8.0.140.0, 8.2.130.0, and 8.3.111.0. Cisco Bug IDs: CSCva86353.

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to trigger a denial of service (DoS) condition on an affected device. This vulnerability is due to improper control of a resource. An attacker with the ability to spoof a trusted IKEv2 site-to-site VPN peer and in possession of valid IKEv2 credentials for that peer could exploit this vulnerability by sending malformed, authenticated IKEv2 messages to an affected device. A successful exploit could allow the attacker to trigger a reload of the device.

A vulnerability in the Akamai Connect feature of Cisco Wide Area Application Services (WAAS) Appliances could allow an unauthenticated, remote attacker to cause a denial-of-service (DoS) condition on an affected device. The vulnerability is due to certain file-handling inefficiencies of the affected system. An attacker could exploit this vulnerability by directing client systems to access a corrupted file that the client systems cannot decompress correctly. A successful exploit could allow the attacker to cause the affected device to crash or hang unexpectedly and result in a DoS condition that may require manual intervention to regain normal operating conditions. Cisco Bug IDs: CSCve82472.

A vulnerability in the memory management 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 (DoS) condition on an affected device. This vulnerability is due to improper resource management when connection rates are high. An attacker could exploit this vulnerability by opening a significant number of connections on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Cisco IOS 12.2(15) and earlier allows remote attackers to cause a denial of service (refused VTY (virtual terminal) connections), via a crafted TCP connection to the Telnet or reverse Telnet port.

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.

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.

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.

A vulnerability in the H.264 decoder function of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a Cisco Meeting Server media process to restart unexpectedly when it receives an illegal H.264 frame. The vulnerability is triggered by an H.264 frame that has an invalid picture parameter set (PPS) value. An attacker could exploit this vulnerability by sending a malformed H.264 frame to the targeted device. An exploit could allow the attacker to cause a denial of service (DoS) condition because the media process could restart. The media session should be re-established within a few seconds, during which there could be a brief interruption in service. Cisco Bug IDs: CSCvg12559.