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 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 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 the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing 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 of an affected device. The vulnerability is due to insufficient input validation during CAPWAP packet processing. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device, resulting in a buffer over-read. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.

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 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 DHCP message handler of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the supervisor to crash, which could result in a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when DHCP version 4 (DHCPv4) messages are parsed. An attacker could exploit this vulnerability by sending a malicious DHCPv4 message to or through a WAN interface of an affected device. A successful exploit could allow the attacker to cause a reload of the affected device. Note: On Cisco cBR-8 Converged Broadband Routers, all of the following are considered WAN interfaces: 10 Gbps Ethernet interfaces 100 Gbps Ethernet interfaces Port channel interfaces that include multiple 10 and/or 100 Gbps Ethernet interfaces

A vulnerability in the IPv6 implementation of Cisco StarOS 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 incoming IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet to an affected device with the goal of reaching the vulnerable section of the input buffer. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic is not affected.

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.

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 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 generic routing encapsulation (GRE) tunnel decapsulation feature 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 a memory handling error when GRE over IPv6 traffic is processed. An attacker could exploit this vulnerability by sending crafted GRE over IPv6 packets with either IPv4 or IPv6 payload through an affected device. A successful exploit could allow the attacker to cause the device to crash, resulting in a DoS condition.

A vulnerability in the resource handling system of Cisco NX-OS Software for Cisco MDS 9000 Series Multilayer Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource usage control. An attacker could exploit this vulnerability by sending traffic to the management interface (mgmt0) of an affected device at very high rates. An exploit could allow the attacker to cause unexpected behaviors such as high CPU usage, process crashes, or even full system reboots of an affected device.

A vulnerability in the DHCP code for the Zero Touch Provisioning feature of Cisco ASR 920 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a format string vulnerability when processing a crafted DHCP packet for Zero Touch Provisioning. An attacker could exploit this vulnerability by sending a specially crafted DHCP packet to an affected device. An exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. This vulnerability affects Cisco ASR 920 Series Aggregation Services Routers that are running an affected release of Cisco IOS XE Software (3.13 through 3.18) and are listening on the DHCP server port. By default, the devices do not listen on the DHCP server port. Cisco Bug IDs: CSCuy56385.

Multiple vulnerabilities in the EnergyWise module of Cisco IOS (12.2 and 15.0 through 15.6) and Cisco IOS XE (3.2 through 3.18) could allow an unauthenticated, remote attacker to cause a buffer overflow condition or a reload of an affected device, leading to a denial of service (DoS) condition. These vulnerabilities are due to improper parsing of crafted EnergyWise packets destined to an affected device. An attacker could exploit these vulnerabilities by sending crafted EnergyWise packets to be processed by an affected device. An exploit could allow the attacker to cause a buffer overflow condition or a reload of the affected device, leading to a DoS condition. Cisco IOS Software and Cisco IOS XE Software support EnergyWise for IPv4 communication. Only IPv4 packets destined to a device configured as an EnergyWise domain member can trigger these vulnerabilities. IPv6 packets cannot be used to trigger these vulnerabilities. Cisco Bug ID CSCut47751.

A vulnerability in the Event Management Service daemon (emsd) of Cisco IOS XR routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability is due to improper handling of gRPC requests. An attacker could exploit this vulnerability by repeatedly sending unauthenticated gRPC requests to the affected device. A successful exploit could allow the attacker to crash the device in such a manner that manual intervention is required to recover. This vulnerability affects all Cisco IOS XR platforms that are running release 6.1.1 of Cisco IOS XR Software when the gRPC service is enabled on the device. The gRPC service is not enabled by default. Cisco Bug IDs: CSCvb14441.

Cisco Wireless LAN Controller (WLC) devices 7.2 before 7.2.115.2, 7.3, and 7.4 before 7.4.110.0 allow remote attackers to cause a denial of service (device restart) via a crafted 802.11 Ethernet frame, aka Bug ID CSCue87929.

The control-plane access-list implementation in Cisco IPS Software before 7.1(8p2)E4 and 7.2 before 7.2(2)E4 allows remote attackers to cause a denial of service (MainApp process outage) via crafted packets to TCP port 7000, aka Bug ID CSCui67394.

A vulnerability in the ingress packet processing function of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services 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 resource allocation when an affected device processes network traffic in software switching mode (punted). An attacker could exploit this vulnerability by sending specific streams of Layer 2 or Layer 3 protocol data units (PDUs) to an affected device. A successful exploit could cause the affected device to run out of buffer resources, which could make the device unable to process or forward traffic, resulting in a DoS condition. The device would need to be restarted to regain functionality.

A vulnerability in the packet processing functionality of Cisco TelePresence Collaboration Endpoint (CE) Software and Cisco RoomOS Software could allow an unauthenticated, 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 crafted H.323 traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to either reboot normally or reboot into maintenance mode, which could result in a DoS condition on the device.

A vulnerability in the Snort rule evaluation function 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 improper handling of the DNS reputation enforcement rule. An attacker could exploit this vulnerability by sending crafted UDP packets through an affected device to force a buildup of UDP connections. A successful exploit could allow the attacker to cause traffic that is going through the affected device to be dropped, resulting in a DoS condition. Note: This vulnerability only affects Cisco FTD devices that are running Snort 3.

On April 20, 2022, the following vulnerability in the ClamAV scanning library versions 0.103.5 and earlier and 0.104.2 and earlier was disclosed: A vulnerability in HTML file parser of Clam AntiVirus (ClamAV) versions 0.104.0 through 0.104.2 and LTS version 0.103.5 and prior versions could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. For a description of this vulnerability, see the ClamAV blog. This advisory will be updated as additional information becomes available.

A vulnerability in the Cisco Fabric Services over IP (CFSoIP) feature 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 is due to insufficient validation of incoming CFSoIP packets. An attacker could exploit this vulnerability by sending crafted CFSoIP packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in IP ingress packet processing of the Cisco Embedded Wireless Controller with Catalyst Access Points Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, causing a denial of service (DoS) condition. The device may experience a performance degradation in traffic processing or high CPU usage prior to the unexpected reload. This vulnerability is due to improper rate limiting of IP packets to the management interface. An attacker could exploit this vulnerability by sending a steady stream of IP traffic at a high rate to the management interface of the affected device. A successful exploit could allow the attacker to cause the device to reload.

A vulnerability in the web services interface for remote access VPN features 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. This vulnerability is due to improper input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a crafted HTTPS request to 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 DNS inspection handler of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service condition (DoS) on an affected device. This vulnerability is due to a lack of proper processing of incoming requests. An attacker could exploit this vulnerability by sending crafted DNS requests at a high rate to an affected device. A successful exploit could allow the attacker to cause the device to stop responding, resulting in a DoS condition.

A vulnerability in the remote access SSL VPN features 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 an affected device. This vulnerability is due to improper validation of errors that are logged as a result of client connections that are made using remote access VPN. An attacker could exploit this vulnerability by sending crafted requests to an affected system. A successful exploit could allow the attacker to cause the affected device to restart, resulting in a DoS condition.

A denial-of-service issue in Cisco Unified IP Conference Station 7937G 1-4-4-0 through 1-4-5-7 allows attackers to remotely disable the device until it is power cycled. Note: We cannot prove this vulnerability exists. Out of an abundance of caution, this CVE is being assigned to better serve our customers and ensure all who are still running this product understand that the product is end of life and should be removed or upgraded. For more information on this, and how to upgrade, refer to the CVE’s reference information

Cisco IOS 12.2 and 12.4, when NAT Skinny Call Control Protocol (SCCP) Fragmentation Support is enabled, allows remote attackers to cause a denial of service (device reload) via segmented SCCP messages, aka CSCsg22426, a different vulnerability than CVE-2008-3811.

The UDP process in Cisco IOS XR 4.3.1 does not free packet memory upon detecting full packet queues, which allows remote attackers to cause a denial of service (memory consumption) via UDP packets to listening ports, aka Bug ID CSCue69413.

The DNS-over-TCP implementation in Cisco IOS 12.2 and 15.0 through 15.3, when NAT is used, allows remote attackers to cause a denial of service (device reload) via a crafted IPv4 DNS TCP stream, aka Bug ID CSCuf28733.

The T1/E1 driver-queue functionality in Cisco IOS 12.2 and 15.0 through 15.3, when an HDLC32 driver is used, allows remote attackers to cause a denial of service (interface queue wedge) via bursty network traffic, aka Bug ID CSCub67465.

A denial-of-service in Cisco Unified IP Conference Station 7937G 1-4-4-0 through 1-4-5-7 allows attackers restart the device remotely through sending specially crafted packets. Note: We cannot prove this vulnerability exists. Out of an abundance of caution, this CVE is being assigned to better serve our customers and ensure all who are still running this product understand that the product is end of life and should be removed or upgraded. For more information on this, and how to upgrade, refer to the CVE’s reference information

Race condition in the IPv6 virtual fragmentation reassembly (VFR) implementation in Cisco IOS 12.2 through 12.4 and 15.0 through 15.3 allows remote attackers to cause a denial of service (device reload or hang) via fragmented IPv6 packets, aka Bug ID CSCud64812.

Memory leak in Cisco Adaptive Security Appliances (ASA) 5500 Series and PIX Security Appliances 8.0 before 8.0(4) and 8.1 before 8.1(2) allows remote attackers to cause a denial of service (memory consumption) via an unspecified sequence of packets, related to the "initialization code for the hardware crypto accelerator."

Cisco IOS 15.0 through 15.3 and IOS XE 3.2 through 3.8, when a VRF interface exists, allows remote attackers to cause a denial of service (interface queue wedge) via crafted UDP RSVP packets, aka Bug ID CSCuf17023.

The Zone-Based Firewall (ZFW) feature in Cisco IOS 15.1 through 15.2, when content filtering or HTTP ALG inspection is enabled, allows remote attackers to cause a denial of service (device reload or hang) via crafted IPv4 HTTP traffic, aka Bug ID CSCtx56174.

Cisco TelePresence MCU devices with software 4.5(1.45) allow remote attackers to cause a denial of service (device reload) via an unspecified series of TCP packets, aka Bug ID CSCur50347.

Cisco IOS XE 3.4 before 3.4.2S and 3.5 before 3.5.1S on 1000 ASR devices allows remote attackers to cause a denial of service (device reload) via malformed ICMP error packets associated with a (1) TCP or (2) UDP session that is under inspection by the Zone-Based Firewall (ZBFW) component, aka Bug ID CSCtt26470.

The web framework on Cisco Web Security Appliance (WSA), Email Security Appliance (ESA), and Content Security Management Appliance (SMA) devices does not properly manage the state of HTTP and HTTPS sessions, which allows remote attackers to cause a denial of service (management GUI outage) via multiple TCP connections, aka Bug IDs CSCuj59411, CSCuf89818, and CSCuh05635.

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.

The PPTP ALG implementation in Cisco IOS XE 3.9 before 3.9.2S on 1000 ASR devices allows remote attackers to cause a denial of service (device reload) by sending many PPTP packets over NAT, aka Bug ID CSCuh19936.

Cisco IOS 12.2 through 12.4 and 15.0 through 15.3, and IOS XE 2.1 through 3.9, allows remote attackers to cause a denial of service (device reload) via crafted DHCP packets that are processed locally by a (1) server or (2) relay agent, aka Bug ID CSCug31561.

Cisco IOS XE 3.9 before 3.9.2S on 1000 ASR devices allows remote attackers to cause a denial of service (device reload) by sending malformed EoGRE packets over (1) IPv4 or (2) IPv6, aka Bug ID CSCuf08269.

Cisco IOS XR 4.0.1 through 4.2.0 for CRS-3 Carrier Routing System allows remote attackers to cause a denial of service (NPU ASIC scan and line-card reload) via crafted IPv6 extension headers, aka Bug ID CSCtx03546.

Memory leak in the TCP input module in Cisco IOS 12.2, 12.4, 15.0, 15.2, 15.3, and 15.4 and IOS XE 3.3.xXO, 3.5.xE, 3.6.xE, 3.8.xS through 3.10.xS before 3.10.5S, and 3.11.xS and 3.12.xS before 3.12.3S allows remote attackers to cause a denial of service (memory consumption or device reload) by sending crafted TCP packets over (1) IPv4 or (2) IPv6, aka Bug ID CSCum94811.