A vulnerability in the Snort 2 and Snort 3 TCP and UDP detection engine of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Appliances could allow an unauthenticated, remote attacker to cause memory corruption, which could cause the Snort detection engine to restart unexpectedly. This vulnerability is due to improper memory management when the Snort detection engine processes specific TCP or UDP packets. An attacker could exploit this vulnerability by sending crafted TCP or UDP packets through a device that is inspecting traffic using the Snort detection engine. A successful exploit could allow the attacker to restart the Snort detection engine repeatedly, which could cause a denial of service (DoS) condition. The DoS condition impacts only the traffic through the device that is examined by the Snort detection engine. The device can still be managed over the network. Note: Once a memory block is corrupted, it cannot be cleared until the Cisco Firepower 2100 Series Appliance is manually reloaded. This means that the Snort detection engine could crash repeatedly, causing traffic that is processed by the Snort detection engine to be dropped until the device is manually reloaded.

A vulnerability in the HTML parser of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to an issue in the C to Rust foreign function interface. An attacker could exploit this vulnerability by submitting a crafted file containing HTML content to be scanned by ClamAV on an affected device. An exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software.

A vulnerability in the VPN and management web servers of the Cisco Adaptive Security Virtual Appliance (ASAv) and Cisco Secure Firewall Threat Defense Virtual (FTDv), formerly Cisco Firepower Threat Defense Virtual, platforms could allow an unauthenticated, remote attacker to cause the virtual devices to run out of system memory, which could cause SSL VPN connection processing to slow down and eventually cease all together. This vulnerability is due to a lack of proper memory management for new incoming SSL/TLS connections on the virtual platforms. An attacker could exploit this vulnerability by sending a large number of new incoming SSL/TLS connections to the targeted virtual platform. A successful exploit could allow the attacker to deplete system memory, resulting in a denial of service (DoS) condition. The memory could be reclaimed slowly if the attack traffic is stopped, but a manual reload may be required to restore operations quickly.

The kernel in Cisco TelePresence Server 3.0 through 4.2(4.18) on Mobility Services Engine (MSE) 8710 devices allows remote attackers to cause a denial of service (panic and reboot) via a crafted sequence of IPv6 packets, aka Bug ID CSCuu46673.

The Wide Area Application Services (WAAS) Express implementation in Cisco IOS 15.1 through 15.5 allows remote attackers to cause a denial of service (device reload) via a crafted TCP segment, aka Bug ID CSCuq59708.

The IKEv2 implementation in Cisco IOS 15.0 through 15.6 and IOS XE 3.3 through 3.17 allows remote attackers to cause a denial of service (device reload) via fragmented packets, aka Bug ID CSCux38417.

The Locator/ID Separation Protocol (LISP) implementation in Cisco IOS 15.1 and 15.2 and NX-OS 4.1 through 6.2 allows remote attackers to cause a denial of service (device reload) via a crafted header in a packet, aka Bug ID CSCuu64279.

Cisco NX-OS 4.0 through 7.3 and 11.0 through 11.2 on 1000v, 2000, 3000, 3500, 5000, 5500, 5600, 6000, 7000, 7700, and 9000 devices allows remote attackers to cause a denial of service (device reload) by leveraging a peer relationship to send a crafted BGP UPDATE message, aka Bug IDs CSCuq77105 and CSCux11417.

The virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (resource exhaustion) via a series of PPTP sessions, related to the persistence of interface descriptor block (IDB) data structures after process termination, aka bug ID CSCdv59309.

Multiple unspecified vulnerabilities in the SSH server in Cisco IOS 12.4 allow remote attackers to cause a denial of service (device restart) via unknown vectors, aka Bug ID (1) CSCsk42419, (2) CSCsk60020, and (3) CSCsh51293.

Memory leak in the virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (memory consumption) via a series of PPTP sessions, related to "dead memory" that remains allocated after process termination, aka bug ID CSCsj58566.

Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper memory resource management while the Snort detection engine is processing ICMP packets. An attacker could exploit this vulnerability by sending a series of ICMP packets through an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device, causing the device to reload.

A vulnerability in an API of the Call Bridge feature of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper handling of large series of message requests. An attacker could exploit this vulnerability by sending a series of messages to the vulnerable API. A successful exploit could allow the attacker to cause the affected device to reload, dropping all ongoing calls and resulting in a DoS condition.

Unspecified vulnerability in the Supervisor Engine 32 (Sup32), Supervisor Engine 720 (Sup720), and Route Switch Processor 720 (RSP720) for multiple Cisco products, when using Multi Protocol Label Switching (MPLS) VPN and OSPF sham-link, allows remote attackers to cause a denial of service (blocked queue, device restart, or memory leak) via unknown vectors.

The DHCPv6 relay implementation in Cisco Adaptive Security Appliance (ASA) software 9.0 before 9.0(4.37), 9.1 before 9.1(6.6), 9.2 before 9.2(4), 9.3 before 9.3(3.5), and 9.4 before 9.4(2) allows remote attackers to cause a denial of service (device reload) via crafted DHCPv6 packets, aka Bug IDs CSCus56252 and CSCus57142.

Unspecified vulnerability in Cisco PIX 500 Series Security Appliance and 5500 Series Adaptive Security Appliance (ASA) before 7.2(3)6 and 8.0(3), when the Time-to-Live (TTL) decrement feature is enabled, allows remote attackers to cause a denial of service (device reload) via a crafted IP packet.

Race condition in the IPv6-to-IPv4 functionality in Cisco IOS 15.3S in the Performance Routing Engine (PRE) module on UBR devices allows remote attackers to cause a denial of service (NULL pointer free and module crash) by triggering intermittent connectivity with many IPv6 CPE devices, aka Bug ID CSCug47366.

A vulnerability in the TCP/IP traffic handling function of the Snort Detection Engine of Cisco Firepower Threat Defense (FTD) Software and Cisco FirePOWER Services could allow an unauthenticated, remote attacker to cause legitimate network traffic to be dropped, resulting in a denial of service (DoS) condition. This vulnerability is due to the improper handling of TCP/IP network traffic. An attacker could exploit this vulnerability by sending a large amount of TCP/IP network traffic through the affected device. A successful exploit could allow the attacker to cause the Cisco FTD device to drop network traffic, resulting in a DoS condition. The affected device must be rebooted to resolve the DoS condition.

A vulnerability with the handling of MPLS traffic for Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause the netstack process to unexpectedly restart, which could cause the device to stop processing network traffic or to reload. This vulnerability is due to lack of proper error checking when processing an ingress MPLS frame. An attacker could exploit this vulnerability by sending a crafted IPv6 packet that is encapsulated within an MPLS frame to an MPLS-enabled interface of the targeted device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition. Note: The IPv6 packet can be generated multiple hops away from the targeted device and then encapsulated within MPLS. The DoS condition may occur when the NX-OS device processes the packet.

The packet-storing feature on Cisco 9900 phones with firmware 9.3(2) does not properly support the RTP protocol, which allows remote attackers to cause a denial of service (device hang) by sending malformed RTP packets after a call is answered, aka Bug ID CSCur39976.

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.

Multiple vulnerabilities in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. These vulnerabilities are due to insufficient validation of CAPWAP packets. An attacker could exploit the vulnerabilities by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition.

A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.

A vulnerability in the proxy service of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to exhaust system memory and cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper memory management in the proxy service of an affected device. An attacker could exploit this vulnerability by establishing a large number of HTTPS connections to the affected device. A successful exploit could allow the attacker to cause the system to stop processing new connections, which could result in a DoS condition. Note: Manual intervention may be required to recover from this situation.

Cisco PIX and ASA appliances with 7.0 through 8.0 software, and Cisco Firewall Services Module (FWSM) 3.1(5) and earlier, allow remote attackers to cause a denial of service (device reload) via a crafted MGCP packet, aka CSCsi90468 (appliance) and CSCsi00694 (FWSM).

Unspecified vulnerability in the Extensible Authentication Protocol (EAP) implementation in Cisco IOS 12.3 and 12.4 on Cisco Access Points and 1310 Wireless Bridges (Wireless EAP devices), IOS 12.1 and 12.2 on Cisco switches (Wired EAP devices), and CatOS 6.x through 8.x on Cisco switches allows remote attackers to cause a denial of service (device reload) via a crafted EAP Response Identity packet.

A vulnerability in the TCP Normalizer of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software operating in transparent mode could allow an unauthenticated, remote attacker to poison MAC address tables, resulting in a denial of service (DoS) vulnerability. This vulnerability is due to incorrect handling of certain TCP segments when the affected device is operating in transparent mode. An attacker could exploit this vulnerability by sending a crafted TCP segment through an affected device. A successful exploit could allow the attacker to poison the MAC address tables in adjacent devices, resulting in network disruption.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, 9.x before 9.1(2)SU2, and 10.0 before 10.0(1)SU1, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (core dump and restart) via crafted SIP INVITE messages, aka Bug ID CSCul20444.

Cisco PIX and ASA appliances with 7.1 and 7.2 software, when configured for TLS sessions to the device, allow remote attackers to cause a denial of service (device reload) via a crafted TLS packet, aka CSCsg43276 and CSCsh97120.

Multiple vulnerabilities in the Cisco ATA 190 Series Analog Telephone Adapter Software could allow an attacker to perform a command injection attack resulting in remote code execution 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.

Cisco IOS XE 3.10.2S on an ASR 1000 device with an Embedded Services Processor (ESP) module, when NAT is enabled, allows remote attackers to cause a denial of service (module crash) via malformed H.323 packets, aka Bug ID CSCup21070.

The Zone-Based Firewall implementation in Cisco IOS 12.4(122)T and earlier does not properly manage session-object structures, which allows remote attackers to cause a denial of service (device reload) via crafted network traffic, aka Bug ID CSCul65003.

Cisco IOS 12.0 through 12.4 allows remote attackers to cause a denial of service via (1) a malformed MGCP packet, which causes a device hang, aka CSCsf08998; a malformed H.323 packet, which causes a device crash, as identified by (2) CSCsi60004 with Proxy Unregistration and (3) CSCsg70474; and a malformed Real-time Transport Protocol (RTP) packet, which causes a device crash, as identified by (4) CSCse68138, related to VOIP RTP Lib, and (5) CSCse05642, related to I/O memory corruption.

Cisco IP Phone 7940 and 7960 with P0S3-08-6-00 firmware, and other SIP firmware before 8.7(0), allows remote attackers to cause a denial of service (device reboot) via (1) a certain sequence of 10 invalid SIP INVITE and OPTIONS messages; or (2) a certain invalid SIP INVITE message that contains a remote tag, followed by a certain set of two related SIP OPTIONS messages.

Cisco 4100 and 4400, Airespace 4000, and Catalyst 6500 and 3750 Wireless LAN Controller (WLC) software before 3.2 20070727, 4.0 before 20070727, and 4.1 before 4.1.180.0 allows remote attackers to cause a denial of service (traffic amplification or ARP storm) via a crafted unicast ARP request that (1) has a destination MAC address unknown to the Layer-2 infrastructure, aka CSCsj69233; or (2) occurs during Layer-3 roaming across IP subnets, aka CSCsj70841.

Cisco 4100 and 4400, Airespace 4000, and Catalyst 6500 and 3750 Wireless LAN Controller (WLC) software 4.1 before 4.1.180.0 allows remote attackers to cause a denial of service (ARP storm) via a broadcast ARP packet that "targets the IP address of a known client context", aka CSCsj50374.

Race condition in the TLS implementation in MainApp in the management interface in Cisco Intrusion Prevention System (IPS) Software before 7.3(3)E4 allows remote attackers to cause a denial of service (process hang) by establishing many HTTPS sessions, aka Bug ID CSCuq40652.

Race condition in Cisco Adaptive Security Appliance (ASA) and PIX 7.1 before 7.1(2)49 and 7.2 before 7.2(2)19, when using "clientless SSL VPNs," allows remote attackers to cause a denial of service (device reload) via "non-standard SSL sessions."

The DNS implementation in Cisco Adaptive Security Appliance (ASA) Software 7.2 before 7.2(5.16), 8.2 before 8.2(5.57), 8.3 before 8.3(2.44), 8.4 before 8.4(7.28), 8.5 before 8.5(1.24), 8.6 before 8.6(1.17), 8.7 before 8.7(1.16), 9.0 before 9.0(4.33), 9.1 before 9.1(6.1), 9.2 before 9.2(3.4), and 9.3 before 9.3(3) allows man-in-the-middle attackers to cause a denial of service (memory consumption or device outage) by triggering outbound DNS queries and then sending crafted responses to these queries, aka Bug ID CSCuq77655.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, and 9.x before 9.1(2)SU2, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (core dump and restart) by improperly terminating SIP TCP connections, aka Bug ID CSCul69819.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU6, 8.6 before 8.6(2a)SU4, and 9.x before 9.1(2)SU2, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (SIP outage) via a crafted UDP packet, aka Bug ID CSCuh25062.

The TFTP server in Cisco IOS 12.2(44)SQ1, 12.2(33)XN1, 12.4(25e)JAM1, 12.4(25e)JAO5m, 12.4(23)JY, 15.0(2)ED1, 15.0(2)EY3, 15.1(3)SVF4a, and 15.2(2)JB1 and IOS XE 2.5.x, 2.6.x, 3.1.xS, 3.2.xS, 3.3.xS, 3.4.xS, and 3.5.xS before 3.6.0S; 3.1.xSG, 3.2.xSG, and 3.3.xSG before 3.4.0SG; 3.2.xSE before 3.3.0SE; 3.2.xXO before 3.3.0XO; 3.2.xSQ; 3.3.xSQ; and 3.4.xSQ allows remote attackers to cause a denial of service (device hang or reload) via multiple requests that trigger improper memory management, aka Bug ID CSCts66733.

The call-handling implementation in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, 9.x before 9.1(2)SU2, and 10.0 before 10.0(1)SU1, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (port consumption) by improperly terminating SIP sessions, aka Bug ID CSCul28089.

Cisco IOS 12.2, 12.4, 15.0, 15.2, and 15.3, when a VRF interface is configured, allows remote attackers to cause a denial of service (interface queue wedge) via crafted ICMPv4 packets, aka Bug ID CSCsi02145.

Multiple vulnerabilities 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 vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to 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 these vulnerabilities, 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.

The Wireless Intrusion Detection (aka WIDS) functionality on Cisco Wireless LAN Controller (WLC) devices allows remote attackers to cause a denial of service (device outage) via crafted packets that are improperly handled during rendering of the Signature Events Summary page, aka Bug ID CSCus46861.

Cisco IOS XR 5.0.1 and 5.2.1 on Network Convergence System (NCS) 6000 devices and 5.1.3 and 5.1.4 on Carrier Routing System X (CRS-X) devices allows remote attackers to cause a denial of service (line-card reload) via malformed IPv6 packets with extension headers, aka Bug ID CSCuq95241.

The Connection Conversation Manager (aka CuCsMgr) process in Cisco Unity Connection 8.5 before 8.5(1)SU7, 8.6 before 8.6(2a)SU4, 9.x before 9.1(2)SU2, and 10.0 before 10.0(1)SU1, when SIP trunk integration is enabled, allows remote attackers to cause a denial of service (core dump and restart) via crafted SIP INVITE messages, aka Bug ID CSCul26267.

Race condition in the Measurement, Aggregation, and Correlation Engine (MACE) implementation in Cisco IOS 15.4(2)T3 and earlier allows remote attackers to cause a denial of service (device reload) via crafted network traffic that triggers improper handling of the timing of process switching and Cisco Express Forwarding (CEF) switching, aka Bug ID CSCul48736.

Race condition in the SSL implementation on Cisco Intrusion Prevention System (IPS) devices allows remote attackers to cause a denial of service by making many management-interface HTTPS connections during the key-regeneration phase of an upgrade, aka Bug ID CSCui25688.