A vulnerability in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) 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 a BGP update message that contains crafted EVPN attributes. An attacker could indirectly exploit the vulnerability by sending BGP EVPN update messages with a specific, malformed attribute to an affected system and waiting for a user on the device to display the EVPN operational routes’ status. If successful, the attacker could 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.

A vulnerability in the ingress traffic manager of Cisco IOS XE Software for Cisco Network Convergence System (NCS) 520 Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition in the web management interface of an affected device. This vulnerability is due to incorrect processing of certain IPv4 TCP traffic that is destined to an affected device. An attacker could exploit this vulnerability by sending a large number of crafted TCP packets to the affected device. A successful exploit could allow the attacker to cause the web management interface to become unavailable, resulting in a DoS condition. Note: This vulnerability does not impact traffic that is going through the device or going to the Management Ethernet interface of the device.

A vulnerability in the Internet Key Exchange version 1 (IKEv1) feature 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. The vulnerability is due to improper management of system memory. An attacker could exploit this vulnerability by sending malicious IKEv1 traffic to an affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

A vulnerability in Cisco WebEx Network Recording Player for WebEx Recording Format (WRF) files could allow an attacker to cause a denial of service (DoS) condition. An attacker could exploit this vulnerability by providing a user with a malicious WRF file via email or URL and convincing the user to open the file. A successful exploit could cause an affected player to crash, resulting in a DoS condition. This vulnerability affects Cisco WebEx Business Suite meeting sites, Cisco WebEx Meetings sites, and Cisco WebEx WRF players. Cisco Bug IDs: CSCve30294, CSCve30301.

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 Cisco Webex Player for Webex Recording Format (WRF) files could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. An attacker could exploit this vulnerability by sending a user a link or email attachment with a malicious WRF file and persuading the user to open the file in the Cisco Webex Player. A successful exploit could cause the affected player to crash, resulting in a DoS condition. For more information about this vulnerability, see the Details section of this security advisory.

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.

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 the detection engine that handles Secure Sockets Layer (SSL) packets for Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition because the Snort process unexpectedly restarts. This vulnerability affects Cisco Firepower System Software prior to the first fixed release when it is configured with an SSL Decrypt-Resign policy. More Information: CSCvb62292. Known Affected Releases: 6.0.1 6.1.0 6.2.0. Known Fixed Releases: 6.2.0 6.1.0.2.

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 IP Service Level Agreement (SLA) responder feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the IP SLA responder to reuse an existing port, resulting in a denial of service (DoS) condition. The vulnerability exists because the IP SLA responder could consume a port that could be used by another feature. An attacker could exploit this vulnerability by sending specific IP SLA control packets to the IP SLA responder on an affected device. The control packets must include the port number that could be used by another configured feature. A successful exploit could allow the attacker to cause an in-use port to be consumed by the IP SLA responder, impacting the feature that was using the port and resulting in a DoS condition.

Cisco Web Security Appliance (WSA) 8.0.7 allows remote HTTP servers to cause a denial of service (memory consumption from stale TCP connections) via crafted responses, aka Bug ID CSCuw10426.

Cisco AsyncOS on Email Security Appliance (ESA) devices with software 8.5.6-073, 8.5.6-074, and 9.0.0-461, when clustering is enabled, allows remote attackers to cause a denial of service (clustering and SSH outage) via a packet flood, aka Bug IDs CSCur13704 and CSCuq05636.

Cisco Email Security Appliance (ESA) devices with software 8.5.6-106 and 9.5.0-201 allow remote attackers to cause a denial of service (per-domain e-mail reception outage) by placing malformed DMARC policy data in DNS TXT records for a domain, aka Bug ID CSCuv14806.

A vulnerability in the IP Service Level Agreements (IP SLA) responder and Two-Way Active Measurement Protocol (TWAMP) features of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause device packet memory to become exhausted or cause the IP SLA process to crash, resulting in a denial of service (DoS) condition. This vulnerability exists because socket creation failures are mishandled during the IP SLA and TWAMP processes. An attacker could exploit this vulnerability by sending specific IP SLA or TWAMP packets to an affected device. A successful exploit could allow the attacker to exhaust the packet memory, which will impact other processes, such as routing protocols, or crash the IP SLA process.

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 the Lightweight Directory Access Protocol (LDAP) feature in 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, resulting in a denial of service (DoS) condition. The vulnerabilities are due to the improper parsing of LDAP packets sent to an affected device. An attacker could exploit these vulnerabilities by sending a crafted LDAP packet, using Basic Encoding Rules (BER), to be processed by an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Cisco IOS XR 5.1 allows remote attackers to cause a denial of service (DHCPv6 daemon crash) via a malformed DHCPv6 packet, aka Bug ID CSCuo59052.

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.

The management implementation on Cisco ONS 15454 controller cards with software 9.8 and earlier allows remote attackers to cause a denial of service (card reset) via crafted packets, aka Bug ID CSCtz50902.

Memory leak in the connection-manager implementation in Cisco Adaptive Security Appliance (ASA) Software 9.1(.3) and earlier allows remote attackers to cause a denial of service (multi-protocol management outage) by making multiple management session requests, aka Bug ID CSCug33233.

A vulnerability in the Session Initiation Protocol (SIP) call processing of Cisco Meeting Server (CMS) software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition of the Cisco Meeting Server. The vulnerability is due to insufficient validation of Session Description Protocol (SDP) messages. An attacker could exploit this vulnerability by sending a crafted SDP message to the CMS call bridge. An exploit could allow the attacker to cause the CMS to reload, causing a DoS condition for all connected clients. Versions prior to 2.3.9 are affected.

Cisco Unified Communications Manager (aka CUCM or Unified CM) allows remote attackers to cause a denial of service (service restart) via a crafted SIP message, aka Bug ID CSCub54349.

A vulnerability in the implementation of the Stream Control Transmission Protocol (SCTP) on Cisco Mobility Management Entity (MME) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an eNodeB that is connected to an affected device. The vulnerability is due to insufficient input validation of SCTP traffic. An attacker could exploit this vulnerability by leveraging a man-in-the-middle position between the eNodeB and the MME and then sending a crafted SCTP message to the MME. A successful exploit would cause the MME to stop sending SCTP messages to the eNodeB, triggering a DoS condition.

The OSPFv3 functionality in Cisco IOS XR 5.1 allows remote attackers to cause a denial of service (process crash) via a malformed LSA Type-1 packet, aka Bug ID CSCuj82176.

A vulnerability in the TCP proxy functionality for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error in TCP-based packet inspection, which could cause the TCP packet to have an invalid Layer 2 (L2)-formatted header. An attacker could exploit this vulnerability by sending a crafted TCP packet sequence to the targeted device. A successful exploit could allow the attacker to cause a DoS condition.

The protocol-inspection feature on Cisco Adaptive Security Appliances (ASA) devices does not properly implement the idle timeout, which allows remote attackers to cause a denial of service (connection-table exhaustion) via crafted requests that use an inspected protocol, aka Bug ID CSCuh13899.

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 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 Cisco Webex Network Recording Player and Cisco Webex Player for Microsoft Windows could allow an attacker to cause a process crash resulting in a Denial of service (DoS) condition for the player application on an affected system. The vulnerability exists due to insufficient validation of certain elements with a Webex recording stored in either the Advanced Recording Format (ARF) or the Webex Recording Format (WRF). An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to cause the Webex player application to crash when trying to view the malicious file. This vulnerability affects Cisco Webex Network Recording Player and Webex Player releases earlier than Release 3.0 MR3 Security Patch 2 and 4.0 MR3.

A vulnerability in the syslog processing engine of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a race condition that may occur when syslog messages are processed. An attacker could exploit this vulnerability by sending a high rate of syslog messages to an affected device. A successful exploit could allow the attacker to cause the Application Server process to crash, resulting in a DoS condition.

A vulnerability in Cisco Webex Network Recording Player and Cisco Webex Player for Microsoft Windows could allow an attacker to cause a process crash resulting in a Denial of service (DoS) condition for the player application on an affected system. The vulnerability exists due to insufficient validation of certain elements with a Webex recording stored in either the Advanced Recording Format (ARF) or the Webex Recording Format (WRF). An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to cause the Webex player application to crash when trying to view the malicious file.

A vulnerability in the way Cisco Webex applications process Universal Communications Format (UCF) files could allow an attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation of UCF media files. An attacker could exploit this vulnerability by sending a user a malicious UCF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit would cause the application to quit unexpectedly.

A vulnerability in the Live Data server of Cisco Unified Contact Center Enterprise could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the affected software improperly manages resources when processing inbound Live Data traffic. An attacker could exploit this vulnerability by sending multiple crafted Live Data packets to an affected device. A successful exploit could cause the affected device to run out of buffer resources, which could result in a stack overflow and cause the affected device to reload, resulting in a DoS condition. Note: The Live Data port in Cisco Unified Contact Center Enterprise devices allows only a single TCP connection. To exploit this vulnerability, an attacker would have to send crafted packets to an affected device before a legitimate Live Data client establishes a connection.

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 email message scanning feature of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a temporary denial of service (DoS) condition on an affected device. The vulnerability is due to inadequate parsing mechanisms for specific email body components. An attacker could exploit this vulnerability by sending a malicious email containing a high number of shortened URLs through an affected device. A successful exploit could allow the attacker to consume processing resources, causing a DoS condition on an affected device. To successfully exploit this vulnerability, certain conditions beyond the control of the attacker must occur.

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 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.

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.

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.

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.

A vulnerability in the RADIUS Change of Authorization (CoA) code of Cisco TrustSec, a feature within Cisco IOS XE Software, could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of a malformed packet. An attacker could exploit this vulnerability by sending a malformed packet to an affected device. A successful exploit could allow the attacker to cause a DoS condition on the affected device.

A vulnerability in the Cisco TrustSec (CTS) Protected Access Credential (PAC) provisioning module of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of attributes in RADIUS messages. An attacker could exploit this vulnerability by sending a malicious RADIUS message to an affected device while the device is in a specific state.

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 WebEx Meetings Player T29.10, when WRF file support is enabled, allows remote attackers to cause a denial of service (application crash) via a crafted file, aka Bug ID CSCuz80455.

A vulnerability in the hardware crypto driver of Cisco IOS XE Software for Cisco 4300 Series Integrated Services Routers and Cisco Catalyst 9800-L Wireless Controllers could allow an unauthenticated, remote attacker to disconnect legitimate IPsec VPN sessions to an affected device. The vulnerability is due to insufficient verification of authenticity of received Encapsulating Security Payload (ESP) packets. An attacker could exploit this vulnerability by tampering with ESP cleartext values as a man-in-the-middle.

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

A vulnerability in the Extensible Messaging and Presence Protocol (XMPP) feature of Cisco Meeting Server software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition for users of XMPP conferencing applications. Other applications and processes are unaffected. The vulnerability is due to improper input validation of XMPP packets. An attacker could exploit this vulnerability by sending crafted XMPP packets to an affected device. An exploit could allow the attacker to cause process crashes and a DoS condition for XMPP conferencing applications.

A vulnerability in Cisco Webex Network Recording Player and Cisco Webex Player for Microsoft Windows could allow an attacker to cause a process crash resulting in a Denial of service (DoS) condition for the player application on an affected system. The vulnerability exists due to insufficient validation of certain elements with a Webex recording stored in either the Advanced Recording Format (ARF) or the Webex Recording Format (WRF). An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to cause the Webex player application to crash when trying to view the malicious file.