Multiple vulnerabilities in Cisco SD-WAN products could allow an unauthenticated, remote attacker to execute denial of service (DoS) attacks against an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Cisco IOS XR 3.8.3, 3.8.4, and 3.9.1 allows remote attackers to cause a denial of service (NetIO process restart or device reload) via a crafted IPv4 packet, aka Bug ID CSCth44147.

Cisco IOS XR 3.6.x, 3.8.x before 3.8.3, and 3.9.x before 3.9.1 does not properly remove sshd_lock files from /tmp/, which allows remote attackers to cause a denial of service (disk consumption) by making many SSHv1 connections, aka Bug ID CSCtd64417.

Unspecified vulnerability in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 6.x before 6.1(5)su2, 7.x before 7.1(5)su1, 8.0 before 8.0(3), and 8.5 before 8.5(1) allows remote attackers to cause a denial of service (process failure) via a malformed SIP message, aka Bug ID CSCtg62855.

Unspecified vulnerability in Cisco Wireless LAN Controller (WLC) software 6.0 before 6.0.200.0, 7.0 before 7.0.98.216, and 7.0.1xx before 7.0.112.0 allows remote attackers to cause a denial of service (device reload) via a sequence of ICMP packets, aka Bug ID CSCth74426.

Unspecified vulnerability in Cisco IOS 12.4, 15.0, and 15.1, and IOS XE 2.5.x through 3.2.x, allows remote attackers to cause a denial of service (device reload) via a crafted SIP message, aka Bug ID CSCth03022.

Memory leak in Cisco Unified Communications Manager (CUCM) 6.x before 6.1(5)su2, 7.x before 7.1(5b)su3, 8.x before 8.0(3a)su1, and 8.5 before 8.5(1), and Cisco IOS 12.4 and 15.1, allows remote attackers to cause a denial of service (memory consumption and process failure or device reload) via a malformed SIP message, aka Bug IDs CSCti75128 and CSCtj09179.

Cisco AireOS 4.1 through 7.4.120.0, 7.5.x, and 7.6.100.0 on Wireless LAN Controller (WLC) devices allows remote attackers to cause a denial of service (device reload) via a crafted HTTP request, aka Bug ID CSCun86747.

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.

Unspecified vulnerability in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 6.x before 6.1(5)su2, 7.x before 7.1(5b)su2, 8.0 before 8.0(3), and 8.5 before 8.5(1) allows remote attackers to cause a denial of service (process failure) via a malformed SIP message, aka Bug ID CSCth39586.

The Internet Streamer application in Cisco Content Delivery System (CDS) with software 2.5.7, 2.5.8, and 2.5.9 before build 126 allows remote attackers to cause a denial of service (Web Engine crash) via a crafted URL, aka Bug IDs CSCtg67333 and CSCth25341.

Memory leak in the Data-link switching (aka DLSw) feature in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xS before 3.1.3S and 3.2.xS before 3.2.1S, when implemented over Fast Sequence Transport (FST), allows remote attackers to cause a denial of service (memory consumption and device reload or hang) via a crafted IP protocol 91 packet, aka Bug ID CSCth69364.

The NAT implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xSG, allows remote attackers to cause a denial of service (device reload or hang) via malformed NetMeeting Directory (aka Internet Locator Service or ILS) LDAP traffic, aka Bug ID CSCtd10712.

A vulnerability in the IP fragment-handling implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak on an affected device. This memory leak could prevent traffic from being processed through the device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper error handling when specific failures occur during IP fragment reassembly. An attacker could exploit this vulnerability by sending crafted, fragmented IP traffic to a targeted device. A successful exploit could allow the attacker to continuously consume memory on the affected device and eventually impact traffic, resulting in a DoS condition. The device could require a manual reboot to recover from the DoS condition. Note: This vulnerability applies to both IP Version 4 (IPv4) and IP Version 6 (IPv6) traffic.

Multiple vulnerabilities in the REST API of Cisco UCS Director and Cisco UCS Director Express for Big Data may allow a remote attacker to bypass authentication or conduct directory traversal attacks on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the Split DNS feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability occurs because the regular expression (regex) engine that is used with the Split DNS feature of affected releases may time out when it processes the DNS name list configuration. An attacker could exploit this vulnerability by trying to resolve an address or hostname that the affected device handles. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the Common Open Policy Service (COPS) engine of Cisco IOS XE Software on Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to crash a device. The vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending a malformed COPS message to the device. A successful exploit could allow the attacker to crash the device.

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated attacker to cause process crashes, which could result in a denial of service (DoS) condition on an affected device. The attack vector is configuration dependent and could be remote or adjacent. For more information about the attack vector, see the Details section of this advisory. The vulnerability is due to insufficient error handling when the affected software parses Cisco Fabric Services messages. An attacker could exploit this vulnerability by sending malicious Cisco Fabric Services messages to an affected device. A successful exploit could allow the attacker to cause a reload of an affected device, which could result in a DoS condition.

A vulnerability in the licensing service of Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.The vulnerability is due to improper handling of system resource values by the affected system. An attacker could exploit this vulnerability by sending malicious requests to the targeted system. A successful exploit could allow the attacker to cause the affected system to become unresponsive, resulting in a DoS condition and preventing the management of dependent devices.

A vulnerability in the DHCP server of Cisco Prime Network Registrar could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation of incoming DHCP traffic. An attacker could exploit this vulnerability by sending a crafted DHCP request to an affected device. A successful exploit could allow the attacker to cause a restart of the DHCP server process, causing a DoS condition.

A vulnerability in the Flexible NetFlow Version 9 packet processor of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers 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 parameters in a Flexible NetFlow Version 9 record. An attacker could exploit this vulnerability by sending a malformed Flexible NetFlow Version 9 packet to the Control and Provisioning of Wireless Access Points (CAPWAP) data port of an affected device. An exploit could allow the attacker to trigger an infinite loop, resulting in a process crash that would cause a reload of the device.

A vulnerability in Cisco Aironet Access Point (AP) Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper handling of clients that are trying to connect to the AP. An attacker could exploit this vulnerability by sending authentication requests from multiple clients to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.

A vulnerability in the Open Shortest Path First (OSPF) implementation of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper memory protection mechanisms while processing certain OSPF packets. An attacker could exploit this vulnerability by sending a series of malformed OSPF packets in a short period of time to an affected device. A successful exploit could allow the attacker to cause a reload of the affected device, resulting in a DoS condition for client traffic that is traversing the device.

Multiple vulnerabilities in the Zone-Based Firewall feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload or stop forwarding traffic through the firewall. The vulnerabilities are due to incomplete handling of Layer 4 packets through the device. An attacker could exploit these vulnerabilities by sending a certain sequence of traffic patterns through the device. A successful exploit could allow the attacker to cause the device to reload or stop forwarding traffic through the firewall, resulting in a denial of service. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the TCP packet processing functionality of Cisco IP Phones could allow an unauthenticated, remote attacker to cause the phone to stop responding to incoming calls, drop connected calls, or unexpectedly reload. The vulnerability is due to insufficient TCP ingress packet rate limiting. An attacker could exploit this vulnerability by sending a high and sustained rate of crafted TCP traffic to the targeted device. A successful exploit could allow the attacker to impact operations of the phone or cause the phone to reload, leading to a denial of service (DoS) condition.

Unspecified vulnerability in Cisco IOS 12.4(24)MD before 12.4(24)MD2 on the Cisco Content Services Gateway Second Generation (aka CSG2) allows remote attackers to cause a denial of service (device hang or reload) via crafted TCP packets, aka Bug ID CSCth17178, a different vulnerability than CVE-2011-0350.

Cisco TelePresence Recording Server devices with software 1.6.x allow remote attackers to cause a denial of service (thread consumption and device outage) via a malformed request, related to an "ad hoc recording" issue, aka Bug ID CSCtf97205.

A vulnerability in the packet processing functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to inefficient memory management. An attacker could exploit this vulnerability by sending a large number of TCP packets to a specific port on an affected device. A successful exploit could allow the attacker to exhaust system memory, which could cause the device to reload unexpectedly. No manual intervention is needed to recover the device after it has reloaded.

A vulnerability in the SIP inspection process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a watchdog timeout and crash during the cleanup of threads that are associated with a SIP connection that is being deleted from the connection list. An attacker could exploit this vulnerability by sending a high rate of crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a watchdog timeout and crash, resulting in a crash and reload of the affected device.

Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 7.0 before 7.0(8.12), 7.1 and 7.2 before 7.2(5.2), 8.0 before 8.0(5.21), 8.1 before 8.1(2.49), 8.2 before 8.2(3.6), and 8.3 before 8.3(2.7) and Cisco PIX Security Appliances 500 series devices, when transparent firewall mode is configured but IPv6 is not configured, allow remote attackers to cause a denial of service (packet buffer exhaustion and device outage) via IPv6 traffic, aka Bug ID CSCtj04707.

A vulnerability in Security Group Tag Exchange Protocol (SXP) in Cisco IOS Software, Cisco IOS XE Software, and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because crafted SXP packets are mishandled. An attacker could exploit this vulnerability by sending specifically crafted SXP packets to the affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in the deep packet inspection (DPI) engine of Cisco SD-WAN vEdge 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 processing of FTP traffic. An attacker could exploit this vulnerability by sending crafted FTP packets through an affected device. A successful exploit could allow the attacker to make the device reboot continuously, causing a DoS condition.

A vulnerability in the Umbrella Connector component of Cisco IOS XE Software for Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to trigger a reload, resulting in a denial of service condition on an affected device. The vulnerability is due to insufficient error handling when parsing DNS requests. An attacker could exploit this vulnerability by sending a series of malicious DNS requests to an Umbrella Connector client interface of an affected device. A successful exploit could allow the attacker to cause a crash of the iosd process, which triggers a reload of the affected device.

A vulnerability in the RESTCONF and NETCONF-YANG access control list (ACL) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect processing of the ACL that is tied to the RESTCONF or NETCONF-YANG feature. An attacker could exploit this vulnerability by accessing the device using RESTCONF or NETCONF-YANG. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

The XML-RPC implementation on Cisco TelePresence Multipoint Switch (CTMS) devices with software 1.0.x, 1.1.x, 1.5.x, 1.6.x, and 1.7.0 allows remote attackers to cause a denial of service (process crash) via a crafted request, aka Bug ID CSCtj44534.

A vulnerability in the Session Initiation Protocol (SIP) of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect handling of incoming SIP traffic. An attacker could exploit this vulnerability by sending a series of SIP packets to an affected device. A successful exploit could allow the attacker to exhaust memory on an affected device, causing it to crash and leading to a DoS condition.

Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.0 before 8.0(5.20), 8.1 before 8.1(2.48), 8.2 before 8.2(3), and 8.3 before 8.3(2.1), when the RIP protocol and the Cisco Phone Proxy functionality are configured, allow remote attackers to cause a denial of service (device reload) via a RIP update, aka Bug ID CSCtg66583.

A vulnerability in the DHCP module of 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 the affected device. The vulnerability is due to incorrect processing of certain DHCP packets. An attacker could exploit this vulnerability by sending a crafted DHCP packet to the affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

A vulnerability in the packet processing of Cisco IOS XE Software for Cisco 4461 Integrated Services Routers could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to incorrect processing of IPv4 or IPv6 traffic to or through an affected device. An attacker could exploit this vulnerability by sending IP traffic to or through an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the Secure Sockets Layer (SSL) VPN feature for Cisco Small Business RV VPN Routers could allow an unauthenticated, remote attacker to cause the device to unexpectedly restart, causing a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request over an SSL connection to the targeted device. A successful exploit could allow the attacker to cause a reload, resulting in a DoS condition.

A vulnerability in Cisco Aironet Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) on an affected device. The vulnerability is due to improper resource management while processing specific packets. An attacker could exploit this vulnerability by sending a series of crafted UDP packets to a specific port on an affected device. A successful exploit could either allow the attacker to tear down the connection between the AP and the wireless LAN controller, resulting in the affected device not being able to process client traffic, or cause the vulnerable device to reload, triggering a DoS condition. After the attack, the affected device should automatically recover its normal functions without manual intervention.

A vulnerability in the web interface of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. An exploit could allow the attacker to cause a DoS condition. Note: This vulnerability applies to IP Version 4 (IPv4) and IP Version 6 (IPv6) HTTP traffic.

A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol handler of Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of CAPWAP packets. An attacker could exploit this vulnerability by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to restart, resulting in a DoS condition.