The DHCP relay agent in Cisco Adaptive Security Appliance (ASA) and PIX 7.2 allows remote attackers to cause a denial of service (dropped packets) via a DHCPREQUEST or DHCPINFORM message that causes multiple DHCPACK messages to be sent from DHCP servers to the agent, which consumes the memory allocated for a local buffer. NOTE: this issue only occurs when multiple DHCP servers are used.

Unspecified vulnerability in Cisco Adaptive Security Appliance (ASA) and PIX 7.1 before 7.1(2)49 and 7.2 before 7.2(2)17 allows remote attackers to cause a denial of service (device reload) via unknown vectors related to VPN connection termination and password expiry.

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 Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to inadequate input validation of incoming CAPWAP packets encapsulating multicast DNS (mDNS) queries. An attacker could exploit this vulnerability by connecting to a wireless network and sending a crafted mDNS query, which would flow through and be processed by the wireless controller. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition.

Multiple Cisco products are affected by a vulnerability in local file management for certain system log files of Cisco collaboration products that could allow an unauthenticated, remote attacker to cause high disk utilization, resulting in a denial of service (DoS) condition. The vulnerability occurs because a certain system log file does not have a maximum size restriction. Therefore, the file is allowed to consume the majority of available disk space on the appliance. An attacker could exploit this vulnerability by sending crafted remote connection requests to the appliance. Successful exploitation could allow the attacker to increase the size of a system log file so that it consumes most of the disk space. The lack of available disk space could lead to a DoS condition in which the application functions could operate abnormally, making the appliance unstable. This vulnerability affects the following Cisco Voice Operating System (VOS)-based products: Emergency Responder, Finesse, Hosted Collaboration Mediation Fulfillment, MediaSense, Prime License Manager, SocialMiner, Unified Communications Manager (UCM), Unified Communications Manager IM and Presence Service (IM&P - earlier releases were known as Cisco Unified Presence), Unified Communication Manager Session Management Edition (SME), Unified Contact Center Express (UCCx), Unified Intelligence Center (UIC), Unity Connection, Virtualized Voice Browser. This vulnerability also affects Prime Collaboration Assurance and Prime Collaboration Provisioning. Cisco Bug IDs: CSCvd10872, CSCvf64322, CSCvf64332, CSCvi29538, CSCvi29543, CSCvi29544, CSCvi29546, CSCvi29556, CSCvi29571, CSCvi31738, CSCvi31741, CSCvi31762, CSCvi31807, CSCvi31818, CSCvi31823.

Unspecified vulnerability in the IPSec Manager Service for Cisco Unified CallManager (CUCM) 5.0 before 5.0(4a)SU1 and Cisco Unified Presence Server (CUPS) 1.0 before 1.0(3) allows remote attackers to cause a denial of service (loss of cluster services) via a "specific UDP packet" to UDP port 8500, aka bug ID CSCsg60949.

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.

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 the TIFF 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.

Cisco Firewall Services Module (FWSM) 3.x before 3.1(3.1) allows remote attackers to cause a denial of service (device reboot) via malformed SNMP requests.

Memory leak in the TCP listener in Cisco IOS 9.x, 10.x, 11.x, and 12.x allows remote attackers to cause a denial of service by sending crafted TCP traffic to an IPv4 address on the IOS device.

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.

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 TCP connection handling functionality of Cisco Remote Expert Manager Software 11.0.0 could allow an unauthenticated, remote attacker to disable TCP ports and cause a denial of service (DoS) condition on an affected system. The vulnerability is due to a lack of rate-limiting functionality in the TCP Listen application of the affected software. An attacker could exploit this vulnerability by sending a crafted TCP traffic stream in which specific types of TCP packets are flooded to an affected device, for example a TCP packet stream in which the TCP FIN bit is set in all the TCP packets. A successful exploit could allow the attacker to cause certain TCP listening ports on the affected system to stop accepting incoming connections for a period of time or until the affected device is restarted, resulting in a DoS condition. In addition, system resources, such as CPU and memory, could be exhausted during the attack. Cisco Bug IDs: CSCva29806.

Cisco PIX 500 and ASA 5500 Series Security Appliances 7.0 before 7.0(4.14) and 7.1 before 7.1(2.1), and the FWSM 2.x before 2.3(4.12) and 3.x before 3.1(3.24), when "inspect http" is enabled, allows remote attackers to cause a denial of service (device reboot) via malformed HTTP traffic.

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.

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.

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 CHM 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.

Cisco FWSM 3.x before 3.1(3.2), when authentication is configured to use "aaa authentication match" or "aaa authentication include", allows remote attackers to cause a denial of service (device reboot) via a long HTTP request.

Cisco PIX 500 and ASA 5500 Series Security Appliances 6.x before 6.3(5.115), 7.0 before 7.0(5.2), and 7.1 before 7.1(2.5), and the FWSM 3.x before 3.1(3.24), when the "inspect sip" option is enabled, allows remote attackers to cause a denial of service (device reboot) via malformed SIP packets.

Cisco IOS XE 3.4 before 3.4.5S, and 3.5 through 3.7 before 3.7.1S, on 1000 series Aggregation Services Routers (ASR) does not properly implement the Cisco Multicast Leaf Recycle Elimination (MLRE) feature, which allows remote attackers to cause a denial of service (card reload) via fragmented IPv6 MVPN (aka MVPNv6) packets, aka Bug ID CSCub34945, a different vulnerability than CVE-2013-1164.

A vulnerability in the Application Visibility and Control (AVC-FNF) feature 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. This vulnerability is due to insufficient packet verification for traffic inspected by the AVC feature. An attacker could exploit this vulnerability by sending crafted packets from the wired network to a wireless client, resulting in the crafted packets being processed by the wireless controller. A successful exploit could allow the attacker to cause a crash and reload of the affected device, resulting in a DoS condition.

Cisco Firewall Services Module (FWSM) 3.x before 3.1(3.11), when the HTTPS server is enabled, allows remote attackers to cause a denial of service (device reboot) via certain HTTPS traffic.

Cisco Unified Presence Server (CUPS) 8.6, 9.0, and 9.1 before 9.1.1 allows remote attackers to cause a denial of service (CPU consumption) via crafted packets to the SIP TCP port, aka Bug ID CSCua89930.

The Smart Install client functionality in Cisco IOS 12.2 and 15.0 through 15.3 on Catalyst switches allows remote attackers to cause a denial of service (device reload) via crafted image list parameters in Smart Install packets, aka Bug ID CSCub55790.

A vulnerability in the HTTP remote procedure call (RPC) service of set-top box (STB) receivers manufactured by Cisco for Yes could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the firmware of an affected device fails to handle certain XML values that are passed to the HTTP RPC service listening on the local subnet of the device. An attacker could exploit this vulnerability by submitting a malformed request to an affected device. A successful attack could cause the affected device to restart, resulting in a DoS condition. Yes has updated the affected devices with firmware that addresses this vulnerability. Customers are not required to take action. Vulnerable Products: This vulnerability affects YesMaxTotal, YesMax HD, and YesQuattro STB devices. Cisco Bug IDs: CSCvd08812.

The management API in the XML API management service in the Manager component in Cisco Unified Computing System (UCS) 1.x before 1.2(1b) allows remote attackers to cause a denial of service (service outage) via a malformed request, aka Bug ID CSCtg48206.

A vulnerability in the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) code of Cisco ASA Software could allow an unauthenticated, remote attacker to cause a reload of the affected system. The vulnerability is due to improper parsing of crafted SSL or TLS packets. An attacker could exploit this vulnerability by sending a crafted packet to the affected system. Note: Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability affects systems configured in routed and transparent firewall mode and in single or multiple context mode. This vulnerability can be triggered by IPv4 and IPv6 traffic. A valid SSL or TLS session is needed to exploit this vulnerability. This vulnerability affects Cisco ASA Software running on the following products: Cisco ASA 1000V Cloud Firewall, Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Cisco Adaptive Security Virtual Appliance (ASAv), Cisco Firepower 9300 ASA Security Module, Cisco ISA 3000 Industrial Security Appliance. Fixed versions: 8.4(7.31) 9.0(4.39) 9.1(7) 9.2(4.6) 9.3(3.8) 9.4(2) 9.5(2). Cisco Bug IDs: CSCuv48243.

Cisco Intrusion Prevention System (IPS) Software in ASA 5500-X IPS-SSP software modules before 7.1(7)sp1E4 allows remote attackers to cause a denial of service (Analysis Engine process hang or device reload) via fragmented (1) IPv4 or (2) IPv6 packets, aka Bug ID CSCue51272.

The authentication-proxy implementation on Cisco Adaptive Security Appliances (ASA) devices with software 7.x before 7.2(5.10), 8.0 before 8.0(5.31), 8.1 and 8.2 before 8.2(5.38), 8.3 before 8.3(2.37), 8.4 before 8.4(5.3), 8.5 and 8.6 before 8.6(1.10), 8.7 before 8.7(1.4), 9.0 before 9.0(1.1), and 9.1 before 9.1(1.2) allows remote attackers to cause a denial of service (device reload) via a crafted URL, aka Bug ID CSCud16590.

Cisco NX-OS on Nexus 5500 devices 4.x and 5.x before 5.0(3)N2(2), Nexus 3000 devices 5.x before 5.0(3)U3(2), and Unified Computing System (UCS) 6200 devices before 2.0(1w) allows remote attackers to cause a denial of service (device reload) by sending a jumbo packet to the management interface, aka Bug IDs CSCtx17544, CSCts10593, and CSCtx95389.

The auth-proxy functionality in Cisco Firewall Services Module (FWSM) software 3.1 and 3.2 before 3.2(20.1), 4.0 before 4.0(15.2), and 4.1 before 4.1(5.1) allows remote attackers to cause a denial of service (device reload) via a crafted URL, aka Bug ID CSCtg02624.

Memory leak in Cisco IOS 12.2, 12.4, 15.0, and 15.1, when Zone-Based Policy Firewall SIP application layer gateway inspection is enabled, allows remote attackers to cause a denial of service (memory consumption or device reload) via malformed SIP messages, aka Bug ID CSCtl99174.

The IP stack in Cisco Intrusion Prevention System (IPS) Software in ASA 5500-X IPS-SSP software and hardware modules before 7.1(5)E4, IPS 4500 sensors before 7.1(6)E4, and IPS 4300 sensors before 7.1(5)E4 allows remote attackers to cause a denial of service (MainApp process hang) via malformed IPv4 packets, aka Bug ID CSCtx18596.

Cisco IOS XE 3.4 before 3.4.4S, 3.5, and 3.6 on 1000 series Aggregation Services Routers (ASR) does not properly implement the Cisco Multicast Leaf Recycle Elimination (MLRE) feature, which allows remote attackers to cause a denial of service (card reload) via fragmented IPv6 multicast packets, aka Bug ID CSCtz97563.

The Wireless Intrusion Prevention System (wIPS) component on Cisco Wireless LAN Controller (WLC) devices with software 7.0 before 7.0.235.0, 7.1 and 7.2 before 7.2.110.0, and 7.3 before 7.3.101.0 allows remote attackers to cause a denial of service (device reload) via crafted IP packets, aka Bug ID CSCtx80743.

Race condition in the VRF-aware NAT feature in Cisco IOS 12.2 through 12.4 and 15.0 through 15.2 allows remote attackers to cause a denial of service (memory consumption) via IPv4 packets, aka Bug IDs CSCtg47129 and CSCtz96745.

The General Responder implementation in the IP Service Level Agreement (SLA) feature in Cisco IOS 15.2 and IOS XE 3.1.xS through 3.4.xS before 3.4.5S and 3.5.xS through 3.7.xS before 3.7.2S allows remote attackers to cause a denial of service (device reload) via crafted (1) IPv4 or (2) IPv6 IP SLA packets on UDP port 1167, aka Bug ID CSCuc72594.

Memory leak in the IKEv1 implementation in Cisco IOS 15.1 allows remote attackers to cause a denial of service (memory consumption) via unspecified (1) IPv4 or (2) IPv6 IKE packets, aka Bug ID CSCth81055.

Cisco Security Agent (CSA) for Linux 4.5 before 4.5.1.657 and 5.0 before 5.0.0.193, as used by Unified CallManager (CUCM) and Unified Presence Server (CUPS), allows remote attackers to cause a denial of service (resource consumption) via a port scan with certain options.

The CallServer component in Cisco Unified Customer Voice Portal (CVP) Software before 9.0.1 ES 11 allows remote attackers to cause a denial of service (call-acceptance outage) via malformed SIP INVITE messages, aka Bug ID CSCua65148.

Cisco Adaptive Security Appliances (ASA) devices with software 9.0 before 9.0(1.2) allow remote attackers to cause a denial of service (device reload) via a crafted field in a DNS message, aka Bug ID CSCuc80080.

Cisco IOS XE 2.x and 3.x before 3.4.5S, and 3.5 through 3.7 before 3.7.1S, on 1000 series Aggregation Services Routers (ASR) allows remote attackers to cause a denial of service (card reload) by sending many crafted L2TP packets, aka Bug ID CSCtz23293.

Cisco Adaptive Security Appliances (ASA) devices with software 7.x before 7.2(5.10), 8.0 before 8.0(5.28), 8.1 and 8.2 before 8.2(5.35), 8.3 before 8.3(2.34), 8.4 before 8.4(4.11), 8.6 before 8.6(1.10), and 8.7 before 8.7(1.3), and Cisco Firewall Services Module (FWSM) software 3.1 and 3.2 before 3.2(24.1) and 4.0 and 4.1 before 4.1(11.1), allow remote attackers to cause a denial of service (device reload) via a crafted IKEv1 message, aka Bug IDs CSCub85692 and CSCud20267.

Cisco Unified Communications Manager (CUCM) 8.6 before 8.6(2a)su2, 8.6 BE3k before 8.6(4) BE3k, and 9.x before 9.0(1) allows remote attackers to cause a denial of service (CPU consumption and GUI and voice outages) via malformed packets to unused UDP ports, aka Bug ID CSCtx43337.

Cisco Wireless LAN Controller (WLC) devices with software 7.0 before 7.0.220.0, 7.1 before 7.1.91.0, and 7.2 before 7.2.103.0 allow remote attackers to cause a denial of service (Access Point reload) via crafted SIP packets, aka Bug ID CSCts87659.

Unspecified vulnerability in Cisco IOS 12.4, when NAT SCCP fragmentation support is enabled, allows remote attackers to cause a denial of service (device reload) via crafted Skinny Client Control Protocol (SCCP) packets, aka Bug ID CSCsy09250.

The VLAN Trunking Protocol (VTP) feature in Cisco IOS 12.1(19) and CatOS allows remote attackers to cause a denial of service by sending a VTP update with a revision value of 0x7FFFFFFF, which is incremented to 0x80000000 and is interpreted as a negative number in a signed context.

Multiple unspecified vulnerabilities in the CSRadius service in Cisco Secure Access Control Server (ACS) for Windows before 4.1 and ACS Solution Engine before 4.1 allow remote attackers to cause a denial of service (crash) via a crafted RADIUS Access-Request packet. NOTE: it has been reported that at least one issue is a heap-based buffer overflow involving the Tunnel-Password attribute.

A vulnerability in the Session Initiation Protocol (SIP) of the Cisco TelePresence Codec (TC) and Collaboration Endpoint (CE) Software could allow an unauthenticated, remote attacker to cause a TelePresence endpoint to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of flow-control mechanisms within the software. An attacker could exploit this vulnerability by sending a flood of SIP INVITE packets to the affected device. An exploit could allow the attacker to impact the availability of services and data of the device, including a complete DoS condition. This vulnerability affects the following Cisco TC and CE platforms when running software versions prior to TC 7.3.8 and CE 8.3.0. Cisco Bug IDs: CSCux94002.