Multiple unspecified vulnerabilities in the home agent (HA) implementation in the (1) Mobile IP NAT Traversal feature and (2) Mobile IPv6 subsystem in Cisco IOS 12.3 through 12.4 allow remote attackers to cause a denial of service (input queue wedge and interface outage) via an ICMP packet, aka Bug ID CSCso05337.

Multiple unspecified vulnerabilities in the (1) Mobile IP NAT Traversal feature and (2) Mobile IPv6 subsystem in Cisco IOS 12.3 through 12.4 allow remote attackers to cause a denial of service (input queue wedge and interface outage) via MIPv6 packets, aka Bug ID CSCsm97220.

A vulnerability in the FTP inspection engine of Cisco 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 vulnerability exists because the affected software fails to release spinlocks when a device is running low on system memory, if the software is configured to apply FTP inspection and an access control rule to transit traffic, and the access control rule is associated with an FTP file policy. An attacker could exploit this vulnerability by sending a high rate of transit traffic through an affected device to cause a low-memory condition on the device. A successful exploit could allow the attacker to cause a software panic on the affected device, which could cause the device to reload and result in a temporary DoS condition.

A vulnerability in the implementation of Traffic Flow Confidentiality (TFC) over IPsec functionality in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error that may occur if the affected software renegotiates the encryption key for an IPsec tunnel when certain TFC traffic is in flight. An attacker could exploit this vulnerability by sending a malicious stream of TFC traffic through an established IPsec tunnel on an affected device. A successful exploit could allow the attacker to cause a daemon process on the affected device to crash, which could cause the device to crash and result in a DoS condition.

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.

Cisco TelePresence Video Communication Server (VCS) X8.5RC4 allows remote attackers to cause a denial of service (CPU consumption or device outage) via a crafted SDP parameter-negotiation request in an SDP session during a SIP connection, aka Bug ID CSCut42422.

Race condition in the Common Classification Engine (CCE) 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 CSCuj96752.

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.

Memory leak in the Cisco Tunneling Control Protocol (cTCP) encapsulation feature in Cisco IOS 12.4, when an Easy VPN (aka EZVPN) server is enabled, allows remote attackers to cause a denial of service (memory consumption and device crash) via a sequence of TCP packets.

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.

Multiple vulnerabilities in the Zone-Based Firewall feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload or stop forwarding traffic through the firewall. The vulnerabilities are due to incomplete handling of Layer 4 packets through the device. An attacker could exploit these vulnerabilities by sending a certain sequence of traffic patterns through the device. A successful exploit could allow the attacker to cause the device to reload or stop forwarding traffic through the firewall, resulting in a denial of service. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the web UI feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a cross-site WebSocket hijacking (CSWSH) attack and cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient HTTP protections in the web UI on an affected device. An attacker could exploit this vulnerability by persuading an authenticated user of the web UI to follow a crafted link. A successful exploit could allow the attacker to corrupt memory on the affected device, forcing it to reload and causing a DoS condition.

A vulnerability with the Border Gateway Protocol (BGP) for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a routing process to crash, which could lead to a denial of service (DoS) condition. This vulnerability is due to an issue with the installation of routes upon receipt of a BGP update. An attacker could exploit this vulnerability by sending a crafted BGP update to an affected device. A successful exploit could allow the attacker to cause the routing process to crash, which could cause the device to reload. This vulnerability applies to both Internal BGP (IBGP) and External BGP (EBGP). Note: The Cisco implementation of BGP accepts incoming BGP traffic from explicitly configured peers only. To exploit this vulnerability, an attacker would need to send a specific BGP update message over an established TCP connection that appears to come from a trusted BGP peer.

Cisco IOS XR 4.1.2 through 5.1.1 on ASR 9000 devices, when a Trident-based line card is used, allows remote attackers to cause a denial of service (NP chip and line card reload) via malformed IPv6 packets, aka Bug ID CSCun71928.

Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices that are running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later. Cisco Bug IDs: CSCuy32360, CSCuz60599.

A vulnerability in the TCP socket code of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a state condition between the socket state and the transmission control block (TCB) state. While this vulnerability potentially affects all TCP applications, the only affected application observed so far is the HTTP server. An attacker could exploit this vulnerability by sending specific HTTP requests at a sustained rate to a reachable IP address of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device.

A vulnerability in the web user interface of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a double-free-in-memory handling by the affected software when specific HTTP requests are processed. An attacker could exploit this vulnerability by sending specific HTTP requests to the web user interface of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device. To exploit this vulnerability, the attacker must have access to the management interface of the affected software, which is typically connected to a restricted management network.

Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices that are running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later. Cisco Bug IDs: CSCuy32360, CSCuz60599.

The (1) Cisco Unified Communications Manager Express; (2) SIP Gateway Signaling Support Over Transport Layer Security (TLS) Transport; (3) Secure Signaling and Media Encryption; (4) Blocks Extensible Exchange Protocol (BEEP); (5) Network Admission Control HTTP Authentication Proxy; (6) Per-user URL Redirect for EAPoUDP, Dot1x, and MAC Authentication Bypass; (7) Distributed Director with HTTP Redirects; and (8) TCP DNS features in Cisco IOS 12.0 through 12.4 do not properly handle IP sockets, which allows remote attackers to cause a denial of service (outage or resource consumption) via a series of crafted TCP packets.

A vulnerability in Cisco AMP for Endpoints Mac Connector Software installed on Apple macOS 10.12 could allow an unauthenticated, remote attacker to cause a kernel panic on an affected system, resulting in a denial of service (DoS) condition. The vulnerability exists if the affected software is running in Block network conviction mode. Exploitation could occur if the system that is running the affected software starts a server process and an address in the IP blacklist cache of the affected software attempts to connect to the affected system. A successful exploit could allow the attacker to cause a kernel panic on the system that is running the affected software, resulting in a DoS condition. Cisco Bug IDs: CSCvk08192.

A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling in DNS name resolution by the affected software. An attacker could exploit this vulnerability by sending specially formatted email messages that are processed by an affected device. A successful exploit could allow the attacker to cause the device to become unreachable from management interfaces or to process additional email messages for a period of time until the device recovers, resulting in a DoS condition. Continued attacks could cause the device to become completely unavailable, resulting in a persistent DoS condition.

A vulnerability in the Snort detection engine integration for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause unlimited memory consumption, which could lead to a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient memory management for certain Snort events. An attacker could exploit this vulnerability by sending a series of crafted IP packets that would generate specific Snort events on an affected device. A sustained attack could cause an out of memory condition on the affected device. A successful exploit could allow the attacker to interrupt all traffic flowing through the affected device. In some circumstances, the attacker may be able to cause the device to reload, resulting in a DoS condition.

A vulnerability in the TCP proxy functionality of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper handling of TCP flows. An attacker could exploit this vulnerability by sending a crafted stream of TCP traffic through 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 implementation of the 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. This vulnerability is due to the incorrect processing of a BGP update message that contains specific EVPN attributes. An attacker could exploit this vulnerability by sending a BGP update message that contains specific EVPN attributes. To exploit this vulnerability, an attacker must control a BGP speaker that has an established trusted peer connection to an affected device that is configured with the address family L2VPN EVPN to receive and process the update message. This vulnerability cannot be exploited by any data that is initiated by clients on the Layer 2 network or by peers that are not configured to accept the L2VPN EVPN address family. 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 updates only from explicitly defined peers. For this vulnerability to be exploited, the malicious BGP update message must either come from a configured, valid BGP peer or be injected by the attacker into the affected BGP network on an existing, valid TCP connection to a BGP peer.

A vulnerability in the implementation of the Resource Public Key Infrastructure (RPKI) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the Border Gateway Protocol (BGP) process to crash, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of a specific RPKI to Router (RTR) Protocol packet header. An attacker could exploit this vulnerability by compromising the RPKI validator server and sending a specifically crafted RTR packet to an affected device. Alternatively, the attacker could use man-in-the-middle techniques to impersonate the RPKI validator server and send a crafted RTR response packet over the established RTR TCP connection to the affected device. A successful exploit could allow the attacker to cause a DoS condition because the BGP process could constantly restart and BGP routing could become unstable.

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.

The IGMP implementation on Cisco Wireless LAN Controller (WLC) devices 4.x, 5.x, 6.x, 7.0 before 7.0.250.0, 7.1, 7.2, and 7.3, when IGMPv3 Snooping is enabled, allows remote attackers to cause a denial of service (memory over-read and device restart) via a crafted field in an IGMPv3 message, aka Bug ID CSCuh33240.

A vulnerability in the SSL/TLS inspection of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series firewalls could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation for certain fields of specific SSL/TLS messages. An attacker could exploit this vulnerability by sending a malformed SSL/TLS message through an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. No manual intervention is needed to recover the device after it has reloaded.

A vulnerability in the Umbrella Connector component of Cisco IOS XE Software for Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to trigger a reload, resulting in a denial of service condition on an affected device. The vulnerability is due to insufficient error handling when parsing DNS requests. An attacker could exploit this vulnerability by sending a series of malicious DNS requests to an Umbrella Connector client interface of an affected device. A successful exploit could allow the attacker to cause a crash of the iosd process, which triggers a reload of the affected device.

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 the Secure Login Enhancements capability of Cisco Nexus 1000V Switch for VMware vSphere could allow an unauthenticated, remote attacker to cause an affected Nexus 1000V Virtual Supervisor Module (VSM) to become inaccessible to users through the CLI. The vulnerability is due to improper resource allocation during failed CLI login attempts when login parameters that are part of the Secure Login Enhancements capability are configured on an affected device. An attacker could exploit this vulnerability by performing a high amount of login attempts against the affected device. A successful exploit could cause the affected device to become inaccessible to other users, resulting in a denial of service (DoS) condition requiring a manual power cycle of the VSM to recover.

A vulnerability in the detection engine reassembly of 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 consumes a high level of CPU resources. Affected Products: This vulnerability affects Cisco Firepower System Software running software releases 6.0.0, 6.1.0, 6.2.0, or 6.2.1 when the device is configured with an SSL policy that has at least one rule specifying traffic decryption. More Information: CSCvc58563. Known Affected Releases: 6.0.0 6.1.0 6.2.0 6.2.1.

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.

Cisco Unity 4.x before 4.2(1)ES161, 5.x before 5.0(1)ES53, and 7.x before 7.0(2)ES8, when using anonymous authentication (aka native Unity authentication), allows remote attackers to cause a denial of service (session exhaustion) via a large number of connections.

A vulnerability in the rate limiter for Bidirectional Forwarding Detection (BFD) traffic of Cisco NX-OS Software for Cisco Nexus 9000 Series Switches could allow an unauthenticated, remote attacker to cause BFD traffic to be dropped on an affected device. This vulnerability is due to a logic error in the BFD rate limiter functionality. An attacker could exploit this vulnerability by sending a crafted stream of traffic through the device. A successful exploit could allow the attacker to cause BFD traffic to be dropped, resulting in BFD session flaps. BFD session flaps can cause route instability and dropped traffic, resulting in a denial of service (DoS) condition. This vulnerability applies to both IPv4 and IPv6 traffic.

Unspecified vulnerability in the VLAN Trunking Protocol (VTP) implementation on Cisco IOS and CatOS, when the VTP operating mode is not transparent, allows remote attackers to cause a denial of service (device reload or hang) via a crafted VTP packet sent to a switch interface configured as a trunk port.

The TCP implementation in (1) Linux, (2) platforms based on BSD Unix, (3) Microsoft Windows, (4) Cisco products, and probably other operating systems allows remote attackers to cause a denial of service (connection queue exhaustion) via multiple vectors that manipulate information in the TCP state table, as demonstrated by sockstress.

Cisco IOS 12.0 through 12.4 on Gigabit Switch Router (GSR) devices (aka 12000 Series routers) allows remote attackers to cause a denial of service (device crash) via a malformed Protocol Independent Multicast (PIM) packet.