A vulnerability in the TCP normalizer of Cisco Adaptive Security Appliance (ASA) Software (8.0 through 8.7 and 9.0 through 9.6) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause Cisco ASA and FTD to drop any further incoming traffic on all interfaces, resulting in a denial of service (DoS) condition. The vulnerability is due to improper limitation of the global out-of-order TCP queue for specific block sizes. An attacker could exploit this vulnerability by sending a large number of unique permitted TCP connections with out-of-order segments. An exploit could allow the attacker to exhaust available blocks in the global out-of-order TCP queue, causing the dropping of any further incoming traffic on all interfaces and resulting in a DoS condition. Cisco Bug IDs: CSCvb46321.

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 connection handling function in 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 is due to improper traffic handling when platform limits are reached. An attacker could exploit this vulnerability by sending a high rate of UDP traffic through an affected device. A successful exploit could allow the attacker to cause all new, incoming connections to be dropped, resulting in a DoS condition.

A vulnerability in the implementation of Border Gateway Protocol (BGP) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to incorrect processing of certain BGP update messages. An attacker could exploit this vulnerability by sending BGP update messages that include a specific set of 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 from explicitly defined peers only. To exploit this vulnerability, 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.

A vulnerability within the Endpoint Learning feature of Cisco Nexus 9000 Series Switches running in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an endpoint device in certain circumstances. The vulnerability is due to improper endpoint learning when packets are received on a specific port from outside the ACI fabric and destined to an endpoint located on a border leaf when Disable Remote Endpoint Learning has been enabled. This can result in a Remote (XR) entry being created for the impacted endpoint that will become stale if the endpoint migrates to a different port or leaf switch. This results in traffic not reaching the impacted endpoint until the Remote entry can be relearned by another mechanism.

A vulnerability in the remote access VPN session manager of Cisco Adaptive Security Appliance (ASA) Software could allow a unauthenticated, remote attacker to cause a denial of service (DoS) condition on the remote access VPN services. The vulnerability is due to an issue with the remote access VPN session manager. An attacker could exploit this vulnerability by requesting an excessive number of remote access VPN sessions. An exploit could allow the attacker to cause a DoS condition.

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 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 implementation of Border Gateway Protocol (BGP) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain BGP update messages. An attacker could exploit this vulnerability by sending BGP update messages that include a specific, malformed attribute 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 this vulnerability, 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.

Multiple vulnerabilities exist in the Cisco Webex Network Recording Player for Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by providing a user with a malicious .arf or .wrf file via email or URL and convincing the user to launch the file in the Webex recording players. Exploitation of these vulnerabilities could cause an affected player to crash, resulting in a denial of service (DoS) condition. The Cisco Webex players are applications that are used to play back Webex meetings that have been recorded by an online meeting attendee. The Webex Network Recording Player for .arf files can be automatically installed when the user accesses a recording that is hosted on a Webex server. The Webex Player for .wrf files can be downloaded manually. These vulnerabilities affect ARF and WRF recording players available from Cisco Webex Meetings Suite sites, Cisco Webex Meetings Online sites, and Cisco Webex Meetings Server. Cisco Bug IDs: CSCvh70253, CSCvh70268, CSCvh72272, CSCvh72281, CSCvh72285, CSCvi60477, CSCvi60485, CSCvi60490, CSCvi60520, CSCvi60529, CSCvi60533.

A vulnerability in the Secure Sockets Layer (SSL) Engine of Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper error handling while processing SSL traffic. An attacker could exploit this vulnerability by sending a large volume of crafted SSL traffic to the vulnerable device. A successful exploit could allow the attacker to degrade the device performance by triggering a persistent high CPU utilization condition. Cisco Bug IDs: CSCvh89340.

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.

A vulnerability in SMART-SSL Accelerator functionality for Cisco Wide Area Application Services (WAAS) 6.2.1, 6.2.1a, and 6.2.3a could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition where the WAN optimization could stop functioning while the process restarts. The vulnerability is due to a Secure Sockets Layer/Transport Layer Security (SSL/TLS) alert being incorrectly handled when in a specific SSL/TLS connection state. An attacker could exploit this vulnerability by establishing a SMART-SSL connection through the targeted device. The attacker would then send a crafted stream of SSL/TLS traffic. An exploit could allow the attacker to cause a DoS condition where WAN optimization could stop processing traffic for a short period of time. Cisco Bug IDs: CSCvb71133.

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.

The Locator/ID Separation Protocol (LISP) implementation in Cisco IOS 15.3(3)S and earlier and IOS XE does not properly validate parameters in ITR control messages, which allows remote attackers to cause a denial of service (CEF outage and packet drops) via malformed messages, aka Bug ID CSCun73782.

A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an NX-API system process to unexpectedly restart. The vulnerability is due to incorrect validation of the HTTP header of a request that is sent to the NX-API. An attacker could exploit this vulnerability by sending a crafted HTTP request to the NX-API on an affected device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition in the NX-API service; however, the Cisco NX-OS device itself would still be available and passing network traffic. Note: The NX-API feature is disabled by default.

Cisco IOS before 15.3(2)T, when scansafe is enabled, allows remote attackers to cause a denial of service (latency) via SYN packets that are not accompanied by SYN-ACK packets from the Scan Safe Tower, aka Bug ID CSCub85451.

Cisco IOS before 15.3(1)T on Cisco 2900 devices, when a VWIC2-2MFT-T1/E1 card is configured for TDM/HDLC mode, allows remote attackers to cause a denial of service (serial-interface outage) via certain Frame Relay traffic, aka Bug ID CSCub13317.

The BGP implementation in Cisco NX-OS does not properly filter AS paths, which allows remote attackers to cause a denial of service (BGP service reset and resync) via a malformed UPDATE message, aka Bug ID CSCtn13065.

A vulnerability in the Session Initiation Protocol (SIP) UDP throttling process of Cisco Unified Communications Manager (Cisco Unified CM) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient rate limiting protection. An attacker could exploit this vulnerability by sending the affected device a high rate of SIP messages. An exploit could allow the attacker to cause the device to reload unexpectedly. The device and services will restart automatically. This vulnerability affects Cisco Unified Communications Manager (CallManager) releases prior to the first fixed release; the following list indicates the first minor release that includes the fix for this vulnerability: 10.5.2.14900-16 11.0.1.23900-5 11.5.1.12900-2. Cisco Bug IDs: CSCuz72455.

A vulnerability in the Data-in-Motion (DMo) process installed with the Cisco IOx application environment could allow an unauthenticated, remote attacker to cause a stack overflow that could allow remote code execution with root privileges in the virtual instance running on an affected device. The vulnerability is due to insufficient bounds checking in the DMo process. An attacker could exploit this vulnerability by sending crafted packets that are forwarded to the DMo process for evaluation. The impacts of a successful exploit are limited to the scope of the virtual instance and do not impact the router that is hosting Cisco IOx. This vulnerability affects the following Cisco 800 Series Industrial Integrated Services Routers: Cisco IR809 and Cisco IR829. Cisco IOx Releases 1.0.0.0 and 1.1.0.0 are vulnerable. Cisco Bug IDs: CSCuy52330.

A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an authenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition. To exploit this vulnerability, the attacker must have the OSPF secret key. This vulnerability is due to heap corruption in OSPF when parsing packets. An attacker could exploit this vulnerability by sending crafted packets to the OSPF service. A successful exploit could allow the attacker to corrupt the heap, causing the affected device to reload, resulting in a DoS condition.

The Control and Provisioning of Wireless Access Points (CAPWAP) protocol implementation on Cisco Wireless LAN Controller (WLC) devices allows remote attackers to cause a denial of service via a crafted CAPWAP packet that triggers a buffer over-read, aka Bug ID CSCuh81880.

The WebVPN CIFS implementation in Cisco Adaptive Security Appliance (ASA) Software 9.0(.4.1) and earlier allows remote CIFS servers to cause a denial of service (device reload) via a long share list, aka Bug ID CSCuj83344.

The MLDP implementation in Cisco IOS 15.3(3)S and earlier on 7600 routers, when many VRFs are configured, allows remote attackers to cause a denial of service (chunk corruption and device reload) by establishing many multicast flows, aka Bug ID CSCue22345.

The Clientless SSL VPN feature in Cisco Adaptive Security Appliance (ASA) Software 8.x before 8.2(5.44), 8.3.x before 8.3(2.39), 8.4.x before 8.4(5.7), 8.6.x before 8.6(1.12), 9.0.x before 9.0(2.6), and 9.1.x before 9.1(1.7) allows remote attackers to cause a denial of service (device reload) via crafted HTTPS requests, aka Bug ID CSCua22709.

Cisco Adaptive Security Appliance (ASA) Software, when certain same-security-traffic and management-access options are enabled, allows remote authenticated users to cause a denial of service (stack overflow and device reload) by using the clientless SSL VPN portal for internal-resource browsing, aka Bug ID CSCui51199.

The Java process in the Impact server in Cisco Prime Central for Hosted Collaboration Solution (HCS) allows remote attackers to cause a denial of service (process crash) via a flood of TCP packets, aka Bug ID CSCug57345.

Buffer overflow in the Active Template Library (ATL) framework in the VPNAPI COM module in Cisco AnyConnect Secure Mobility Client 2.x allows user-assisted remote attackers to execute arbitrary code via a crafted HTML document, aka Bug ID CSCuj58139.

Multiple vulnerabilities exist in the Link Layer Discovery Protocol (LLDP) implementation for Cisco Small Business RV Series Routers. An unauthenticated, adjacent attacker could execute arbitrary code or cause an affected router to leak system memory or reload. A memory leak or device reload would cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory. Note: LLDP is a Layer 2 protocol. To exploit these vulnerabilities, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).

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 IOS XR allows local users to cause a denial of service (Silicon Packet Processor memory corruption, improper mutex handling, and device reload) by starting an outbound flood of large ICMP Echo Request packets and stopping this with a CTRL-C sequence, aka Bug ID CSCui60347.

Cisco Aironet 3600 access points allow remote attackers to cause a denial of service (memory corruption and device crash) by disrupting Cisco Wireless LAN Controller communication and consequently forcing many transitions from FlexConnect mode to Standalone mode, aka Bug ID CSCuh71210.

Buffer overflow in an unspecified Android API on the Cisco Desktop Collaboration Experience DX650 allows attackers to execute arbitrary code via vectors that leverage incorrect memory allocation, aka Bug IDs CSCuf93957, CSCug22352, and CSCug22462.

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.

Buffer overflow in Cisco Unified Communications Manager (Unified CM) 7.1(x) before 7.1(5b)su6, 8.5(x) before 8.5(1)su6, 8.6(x) before 8.6(2a)su3, and 9.x before 9.1(2) allows remote authenticated users to execute arbitrary code via unspecified vectors, aka Bug ID CSCud54358.

Buffer overflow in srtp.c in libsrtp in srtp 1.4.5 and earlier allows remote attackers to cause a denial of service (crash) via vectors related to a length inconsistency in the crypto_policy_set_from_profile_for_rtp and srtp_protect functions.

The TCP implementation in Cisco IOS does not properly implement the transitions from the ESTABLISHED state to the CLOSED state, which allows remote attackers to cause a denial of service (flood of ACK packets) via a crafted series of ACK and FIN packets, aka Bug ID CSCtz14399.

Stack-based buffer overflow in Cisco WebEx Recording Format (WRF) player T27 LD before SP32 EP16, T27 L10N before SP32_ORION111, and T28 before T28.8 allows remote attackers to execute arbitrary code via a crafted WRF file, aka Bug ID CSCuc27645.

Multiple buffer overflows in the Cisco Discovery Protocol (CDP) implementation in Cisco NX-OS on Nexus 7000 devices 4.x and 5.x before 5.2(4) and 6.x before 6.1(1), Nexus 5000 and 5500 devices 4.x and 5.x before 5.1(3)N1(1), Nexus 4000 devices before 4.1(2)E1(1h), Nexus 3000 devices 5.x before 5.0(3)U3(1), Nexus 1000V devices 4.x before 4.2(1)SV1(5.1), MDS 9000 devices 4.x and 5.x before 5.2(4), Unified Computing System (UCS) 6100 and 6200 devices before 2.0(2m), and Connected Grid Router (CGR) 1000 devices before CG4(1) allow remote attackers to execute arbitrary code via malformed CDP packets, aka Bug IDs CSCtu10630, CSCtu10551, CSCtu10550, CSCtw56581, CSCtu10548, CSCtu10544, and CSCuf61275.

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.

Buffer overflow in the exception handler in Cisco WebEx Recording Format (WRF) player T27 LD before SP32 EP16, T27 L10N before SP32_ORION111, and T28 before T28.8 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted WRF file, aka Bug ID CSCuc27639.

The ITM web server in Cisco Prime Central for Hosted Collaboration Solution (HCS) allows remote attackers to cause a denial of service (temporary HTTP service outage) via a flood of TCP packets, aka Bug ID CSCuh36313.

Buffer overflow in Cisco WebEx Recording Format (WRF) player T27 LD before SP32 EP16, T27 L10N before SP32_ORION111, and T28 before T28.8 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted DHT index value in JPEG data within a WRF file, aka Bug ID CSCuc24503.

Cisco Adaptive Security Appliance (ASA) Software 8.2.x before 8.2(5.46), 8.3.x before 8.3(2.39), 8.4.x before 8.4(7), 8.5.x before 8.5(1.18), 8.6.x before 8.6(1.12), 8.7.x before 8.7(1.7), 9.0.x before 9.0(3.3), and 9.1.x before 9.1(1.8), when the DNS ALPI engine is enabled for TCP, allows remote attackers to cause a denial of service (device reload) via crafted TCP DNS packets, aka Bug ID CSCug03975.

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.

The HTTP Profiler on the Cisco Aironet Access Point with software 15.2 and earlier does not properly manage buffers, which allows remote attackers to cause a denial of service (device reload) via crafted HTTP requests, aka Bug ID CSCuc62460.