A vulnerability in the Secure Sockets Layer (SSL) VPN feature of Cisco Adaptive Security Appliance (ASA) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition that prevents the creation of new SSL/Transport Layer Security (TLS) connections to an affected device. The vulnerability is due to incorrect handling of Base64-encoded strings. An attacker could exploit this vulnerability by opening many SSL VPN sessions to an affected device. The attacker would need to have valid user credentials on the affected device to exploit this vulnerability. A successful exploit could allow the attacker to overwrite a special system memory location, which will eventually result in memory allocation errors for new SSL/TLS sessions to the device, preventing successful establishment of these sessions. A reload of the device is required to recover from this condition. Established SSL/TLS connections to the device and SSL/TLS connections through the device are not affected. Note: Although this vulnerability is in the SSL VPN feature, successful exploitation of this vulnerability would affect all new SSL/TLS sessions to the device, including management sessions.

Multiple vulnerabilities in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker with read-only privileges to cause the web UI software to become unresponsive and consume vty line instances, resulting in a denial of service (DoS) condition. These vulnerabilities are due to insufficient error handling in the web UI. An attacker could exploit these vulnerabilities by sending crafted HTTP packets to an affected device. A successful exploit could allow the attacker to cause the web UI software to become unresponsive and consume all available vty lines, preventing new session establishment and resulting in a DoS condition. Manual intervention would be required to regain web UI and vty session functionality. Note: These vulnerabilities do not affect the console connection.

A vulnerability in the Secure Shell (SSH) subsystem of Cisco Small Business Managed Switches software could allow an authenticated, remote attacker to cause a reload of the affected switch, resulting in a denial of service (DoS) condition. The vulnerability is due to improper processing of SSH connections. An attacker could exploit this vulnerability by logging in to an affected switch via SSH and sending a malicious SSH message. This vulnerability affects the following Cisco products when SSH is enabled: Small Business 300 Series Managed Switches, Small Business 500 Series Stackable Managed Switches, 350 Series Managed Switches, 350X Series Stackable Managed Switches, 550X Series Stackable Managed Switches, ESW2 Series Advanced Switches. Cisco Bug IDs: CSCvb48377.

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.

Multiple buffer overflows in the administrative web interface in Cisco Unified Computing System (UCS) allow remote authenticated users to cause a denial of service (memory corruption and session termination) via long string values for unspecified parameters, aka Bug ID CSCtg20751.

Cisco Unity Connection (UC) 7.1, 8.0, and 8.5 allows remote authenticated users to cause a denial of service (resource consumption and administration outage) via extended use of the product, aka Bug ID CSCtd79132.

Memory leak on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.2 through 8.4 allows remote authenticated users to cause a denial of service (memory consumption and blank response page) by using the clientless WebVPN feature, aka Bug ID CSCth34278.

Cisco Unified Computing System (UCS) 1.4 and 2.0 allows remote authenticated users to cause a denial of service (device reload) via a malformed SNMP request to a Fabric Interconnect (FI) device, aka Bug ID CSCts32463.

A vulnerability in the Link Layer Discovery Protocol (LLDP) message parser of Cisco IOS Software and Cisco IOS XE Software could allow an attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to improper initialization of a buffer. An attacker could exploit this vulnerability via any of the following methods: An authenticated, remote attacker could access the LLDP neighbor table via either the CLI or SNMP while the device is in a specific state. An unauthenticated, adjacent attacker could corrupt the LLDP neighbor table by injecting specific LLDP frames into the network and then waiting for an administrator of the device or a network management system (NMS) managing the device to retrieve the LLDP neighbor table of the device via either the CLI or SNMP. An authenticated, adjacent attacker with SNMP read-only credentials or low privileges on the device CLI could corrupt the LLDP neighbor table by injecting specific LLDP frames into the network and then accessing the LLDP neighbor table via either the CLI or SNMP. A successful exploit could allow the attacker to cause the affected device to crash, resulting in a reload of the device.

Cisco Unified Computing System (UCS) 1.4 and 2.0 allows remote authenticated users to cause a denial of service (device reload) via a malformed SNMP request to a Fabric Interconnect (FI) device, aka Bug ID CSCts32452.

Unspecified vulnerability on Cisco Adaptive Security Appliances (ASA) 5580 series devices with software before 8.1(2) allows remote authenticated users to cause a denial of service (console hang) via a login action during failover replication, aka Bug ID CSCsq80095.

A vulnerability in the cluster database (CDB) management component of Cisco Expressway Series Software and Cisco TelePresence Video Communication Server (VCS) Software could allow an authenticated, remote attacker to cause the CDB process on an affected system to restart unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability is due to incomplete input validation of URL requests by the REST API of the affected software. An attacker could exploit this vulnerability by sending a crafted URL to the REST API of the affected software on an affected system. A successful exploit could allow the attacker to cause the CDB process on the affected system to restart unexpectedly, resulting in a temporary DoS condition. Cisco Bug IDs: CSCve77571.

Cisco Secure Access Control Server (ACS) Solution Engine 5.7(0.15) allows remote authenticated users to cause a denial of service (SSH screen process crash) via crafted (1) CLI or (2) GUI commands, aka Bug ID CSCuw24694.

A vulnerability in filesystem usage management for Cisco Firepower Device Manager (FDM) Software could allow an authenticated, remote attacker to exhaust filesystem resources, resulting in a denial of service (DoS) condition on an affected device. This vulnerability is due to the insufficient management of available filesystem resources. An attacker could exploit this vulnerability by uploading files to the device and exhausting available filesystem resources. A successful exploit could allow the attacker to cause database errors and cause the device to become unresponsive to web-based management. Manual intervention is required to free filesystem resources and return the device to an operational state.

A vulnerability in the API of Cisco Meeting Server could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because requests that are sent to the API are not properly validated. An attacker could exploit this vulnerability by sending a malicious request to the API. A successful exploit could allow the attacker to cause all participants on a call to be disconnected, resulting in a DoS condition.

A vulnerability in the web proxy functionality of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation mechanisms for certain fields in HTTP/HTTPS requests sent through an affected device. A successful attacker could exploit this vulnerability by sending a malicious HTTP/HTTPS request through an affected device. An exploit could allow the attacker to force the device to stop processing traffic, resulting in a DoS condition.

A vulnerability in the Virtual Shell (VSH) session management for Cisco NX-OS Software could allow an authenticated, remote attacker to cause a VSH process to fail to delete upon termination. This can lead to a build-up of VSH processes that overtime can deplete system memory. When there is no system memory available, this can cause unexpected system behaviors and crashes. The vulnerability is due to the VSH process not being properly deleted when a remote management connection to the device is disconnected. An attacker could exploit this vulnerability by repeatedly performing a remote management connection to the device and terminating the connection in an unexpected manner. A successful exploit could allow the attacker to cause the VSH processes to fail to delete, which can lead to a system-wide denial of service (DoS) condition. The attacker must have valid user credentials to log in to the device using the remote management connection.

A vulnerability in the WebVPN service of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper management of authenticated sessions in the WebVPN portal. An attacker could exploit this vulnerability by authenticating with valid credentials and accessing a specific URL in the WebVPN portal. A successful exploit could allow the attacker to cause the device to reload, resulting in a temporary DoS condition.

A vulnerability in Cisco Meeting Server could allow an authenticated, remote attacker to cause a partial denial of service (DoS) to Cisco Meetings application users who are paired with a Session Initiation Protocol (SIP) endpoint. The vulnerability is due to improper validation of coSpaces configuration parameters. An attacker could exploit this vulnerability by inserting crafted strings in specific coSpace parameters. An exploit could allow the attacker to prevent clients from joining a conference call in the affected coSpace. Versions prior to 2.4.3 are affected.

A vulnerability in the phone book feature of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to cause the CPU to increase to 100% utilization, causing a denial of service (DoS) condition on an affected system. The vulnerability is due to improper handling of the XML input. An attacker could exploit this vulnerability by sending a Session Initiation Protocol (SIP) message with a crafted XML payload to an affected device. A successful exploit could allow the attacker to exhaust CPU resources, resulting in a DoS condition. Manual intervention may be required to recover the device. This vulnerability is fixed in Cisco Expressway Series and Cisco TelePresence Video Communication Server Releases X12.5.1 and later.

A vulnerability in the implementation of the Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition in the IS–IS process. The vulnerability is due to improper handling of a Simple Network Management Protocol (SNMP) request for specific Object Identifiers (OIDs) by the IS–IS process. An attacker could exploit this vulnerability by sending a crafted SNMP request to the affected device. A successful exploit could allow the attacker to cause a DoS condition in the IS–IS process.

A vulnerability in the web interface of Cisco Wireless LAN Controller Software could allow a low-privileged, authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists due to a failure of the HTTP parsing engine to handle specially crafted URLs. An attacker could exploit this vulnerability by authenticating with low privileges to an affected controller and submitting the crafted URL to the web interface of the affected device. Conversely, an unauthenticated attacker could exploit this vulnerability by persuading a user of the web interface to click the crafted URL. A successful exploit could allow the attacker to cause an unexpected restart of the device, resulting in a DoS condition.

A vulnerability in the Operations, Administration, Maintenance and Provisioning (OAMP) OpsConsole Server for Cisco Unified Customer Voice Portal (CVP) could allow an authenticated, remote attacker to execute Insecure Direct Object Reference actions on specific pages within the OAMP application. The vulnerability is due to insufficient input validation on specific pages of the OAMP application. An attacker could exploit this vulnerability by authenticating to Cisco Unified CVP and sending crafted HTTP requests. A successful exploit could allow an attacker with administrator or read-only privileges to learn information outside of their expected scope. An attacker with administrator privileges could modify certain configuration details of resources outside of their defined scope, which could result in a denial of service (DoS) condition.

A vulnerability in the web-based management interface of Cisco SPA100 Series Analog Telephone Adapters (ATAs) could allow an authenticated, remote attacker to cause a denial of service condition on an affected device. The vulnerability is due to improper validation of user-supplied requests to the web-based management interface. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface of an affected device. A successful exploit could allow the attacker to cause the device to stop responding, requiring manual intervention for recovery.

A vulnerability in the web-based management interface of Cisco IC3000 Industrial Compute Gateway could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the affected software improperly manages system resources. An attacker could exploit this vulnerability by opening a large number of simultaneous sessions on the web-based management interface of an affected device. A successful exploit could allow the attacker to cause a DoS condition of the web-based management interface, preventing normal management operations.

A vulnerability in the Secure Copy (SCP) feature of Cisco Adaptive Security Appliance (ASA) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to the use of an incorrect data type for a length variable. An attacker could exploit this vulnerability by initiating the transfer of a large file to an affected device via SCP. To exploit this vulnerability, the attacker would need to have valid privilege level 15 credentials on the affected device. A successful exploit could allow the attacker to cause the length variable to roll over, which could cause the affected device to crash.

A vulnerability in the web interface of Cisco Integrated Management Controller (IMC) Supervisor and Cisco UCS Director could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient restrictions on the size or total amount of resources allowed via the web interface. An attacker who has valid credentials for the application could exploit this vulnerability by sending a crafted or malformed HTTP request to the web interface. A successful exploit could allow the attacker to cause oversubscription of system resources or cause a component to become unresponsive, resulting in a DoS condition.

A vulnerability in the management REST API of Cisco Industrial Network Director (IND) could allow an authenticated, remote attacker to cause the CPU utilization to increase to 100 percent, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of requests sent to the REST API. An attacker could exploit this vulnerability by sending a crafted request to the REST API. A successful exploit could allow the attacker to cause a permanent DoS condition that is due to high CPU utilization. Manual intervention may be required to recover the Cisco IND.

A vulnerability in the web UI of Cisco SD-WAN vManage Software could allow an authenticated, remote attacker to inject arbitrary commands on an affected system and cause a denial of service (DoS) condition. This vulnerability is due to improper input validation of user-supplied input to the device template configuration. An attacker could exploit this vulnerability by submitting crafted input to the device template configuration. A successful exploit could allow the attacker to cause a DoS condition on the affected system.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for Mac, and Cisco Jabber for mobile platforms could allow an attacker to access sensitive information or cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the web-based management interface of Cisco SD-WAN vManage Software could allow an authenticated, remote attacker to consume excessive system memory and cause a denial of service (DoS) condition on an affected system. The vulnerability is due to inefficient memory management. An attacker could exploit this vulnerability by sending a large number of crafted HTTP requests to the affected web-based management interface. A successful exploit could allow the attacker to exhaust system memory, which could cause the system to stop processing new connections and could result in a DoS condition.

A vulnerability in the Simple Network Management Protocol (SNMP) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending a crafted SNMP request to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

The self-service application in Cisco Unified Communications Domain Manager (CUCDM) 10.6(1) allows remote authenticated users to cause a denial of service (subapplication outage) via malformed requests, aka Bug ID CSCuu10981.

Cisco IOS XR 5.1.1.K9SEC allows remote authenticated users to cause a denial of service (vty error, and SSH and TELNET outage) via a crafted disconnect action within an SSH session, aka Bug ID CSCul63127.

The Tomcat throttling feature in Cisco Unified Communications Manager 10.5(1.99995.9) allows remote authenticated users to cause a denial of service (management outage) by sending many requests, aka Bug ID CSCuu99709.

The XML parser in Cisco TelePresence Management Suite (TMS) 14.3(.2) and earlier does not properly handle external entities, which allows remote authenticated users to cause a denial of service via POST requests, aka Bug ID CSCus51494.

The SNMPv2 implementation in Cisco IOS XR allows remote authenticated users to cause a denial of service (snmpd daemon reload) via a malformed SNMP packet, aka Bug ID CSCur25858.

snmpd in Cisco IOS XR 5.1 and earlier allows remote authenticated users to cause a denial of service (process reload) via a malformed SNMPv2 packet, aka Bug ID CSCun67791.

Cisco Identity Services Engine (ISE) 1.2(.1 patch 2) and earlier does not properly handle deadlock conditions during reception of crafted RADIUS accounting packets from multiple NAS devices, which allows remote authenticated users to cause a denial of service (RADIUS outage) by sourcing these packets from two origins, aka Bug ID CSCuo56780.

The session-termination functionality on Cisco ONS 15454 controller cards with software 9.6 and earlier does not initialize an unspecified pointer, which allows remote authenticated users to cause a denial of service (card reset) via crafted session-close actions, aka Bug ID CSCug97416.

The SNMP module in Cisco IOS XR allows remote authenticated users to cause a denial of service (process restart) via crafted SNMP packets, aka Bug ID CSCue69472.

A vulnerability in the Bulk Administration Tool (BAT) for Cisco Unity Connection could allow an authenticated, remote attacker to cause high disk utilization, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software does not restrict the maximum size of certain files that can be written to disk. An attacker who has valid administrator credentials for an affected system could exploit this vulnerability by sending a crafted, remote connection request to an affected system. A successful exploit could allow the attacker to write a file that consumes most of the available disk space on the system, causing application functions to operate abnormally and leading to a DoS condition.

A vulnerability in the configuration of the Pluggable Authentication Module (PAM) used in Cisco Firepower Threat Defense (FTD) Software, Cisco Firepower Management Center (FMC) Software, and Cisco FXOS Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper resource management in the context of user session management. An attacker could exploit this vulnerability by connecting to an affected system and performing many simultaneous successful Secure Shell (SSH) logins. A successful exploit could allow the attacker to exhaust system resources and cause the device to reload, resulting in a DoS condition. To exploit this vulnerability, the attacker needs valid user credentials on the system.

Multiple vulnerabilities in Cisco SD-WAN vEdge Software could allow an attacker to execute arbitrary code as the root user or cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the Simple Network Management Protocol (SNMP) punt handling function of Cisco cBR-8 Converged Broadband Routers could allow an authenticated, remote attacker to overload a device punt path, resulting in a denial of service (DoS) condition. This vulnerability is due to the punt path being overwhelmed by large quantities of SNMP requests. An attacker could exploit this vulnerability by sending a large number of SNMP requests to an affected device. A successful exploit could allow the attacker to overload the device punt path, resulting in a DoS condition.

A vulnerability in service logging for Cisco Prime Service Catalog could allow an authenticated, remote attacker to deny service to the user interface. The vulnerability is due to exhaustion of disk space. An attacker could exploit this vulnerability by performing certain operations that lead to excessive logging. A successful exploit could allow the attacker to deny service to the user interface. Cisco Bug IDs: CSCvd39568.

Cisco IOS Unified Border Element (CUBE) in Cisco IOS before 15.3(2)T allows remote authenticated users to cause a denial of service (input queue wedge) via a crafted series of RTCP packets, aka Bug ID CSCuc42518.

A vulnerability in the Cisco Webex Teams client for Windows could allow an authenticated, remote attacker to cause the client to crash, resulting in a denial of service (DoS) condition. The attacker needs a valid developer account to exploit this vulnerability. The vulnerability is due to insufficient input validation when processing received adaptive cards. The attacker could exploit this vulnerability by sending an adaptive card with malicious content to an existing user of the Cisco Webex Teams client for Windows. A successful exploit could allow the attacker to cause the targeted user's client to crash continuously. This vulnerability was introduced in Cisco Webex Teams client for Windows Release 3.0.13131.