Cisco IOS XE before 3.1.2S on ASR 1000 devices mishandles the automatic setup of Virtual Fragment Reassembly (VFR) by certain firewall and NAT components, which allows remote attackers to cause a denial of service (Embedded Services Processor crash) via crafted IP packets, aka Bug IDs CSCtf87624, CSCte93229, CSCtd19103, and CSCti63623.

A vulnerability in the Network Time Protocol (NTP) feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to excessive use of system resources when the affected device is logging a drop action for received MODE_PRIVATE (Mode 7) NTP packets. An attacker could exploit this vulnerability by flooding the device with a steady stream of Mode 7 NTP packets. A successful exploit could allow the attacker to cause high CPU and memory usage on the affected device, which could cause internal system processes to restart or cause the affected device to unexpectedly reload. Note: The NTP feature is enabled by default.

A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 8800 Series could allow an unauthenticated, remote attacker to cause high disk utilization, resulting in a denial of service (DoS) condition. The vulnerability exists because the affected software does not restrict the maximum size of certain files that can be written to disk. An attacker who has valid administrator credentials for an affected system could exploit this vulnerability by sending a crafted, remote connection request to an affected system. A successful exploit could allow the attacker to write a file that consumes most of the available disk space on the system, causing application functions to operate abnormally and leading to a DoS condition. This vulnerability affects Cisco IP Phone 8800 Series products running a SIP Software release prior to 12.5(1)SR1.

Cisco NX-OS 7.1(1)N1(1) on Nexus 5500, 5600, and 6000 devices does not properly validate PDUs in SNMP packets, which allows remote attackers to cause a denial of service (SNMP application restart) via a crafted packet, aka Bug ID CSCut84645.

A vulnerability in the Network Address Translation 64 (NAT64) functions of Cisco IOS Software could allow an unauthenticated, remote attacker to cause either an interface queue wedge or a device reload. The vulnerability is due to the incorrect handling of certain IPv4 packet streams that are sent through the device. An attacker could exploit this vulnerability by sending specific IPv4 packet streams through the device. An exploit could allow the attacker to either cause an interface queue wedge or a device reload, resulting in a denial of service (DoS) condition.

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.

A vulnerability in the software cryptography module of the Cisco Adaptive Security Virtual Appliance (ASAv) and Firepower 2100 Series running Cisco Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause an unexpected reload of the device that results in a denial of service (DoS) condition. The vulnerability is due to a logic error with how the software cryptography module handles IPsec sessions. An attacker could exploit this vulnerability by creating and sending traffic in a high number of IPsec sessions through the targeted device. A successful exploit could cause the device to reload and result in a DoS condition.

A vulnerability in the Event Management Service daemon (emsd) of Cisco IOS XR 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 gRPC requests. An attacker could exploit this vulnerability by repeatedly sending unauthenticated gRPC requests to the affected device. A successful exploit could cause the emsd process to crash, resulting in a DoS condition. Resolved in Cisco IOS XR 6.5.1 and later.

A vulnerability in the web interface of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to trigger high CPU usage, resulting in a denial of service (DoS) condition. The vulnerability is due to improper handling of Secure Sockets Layer (SSL) renegotiation requests. An attacker could exploit this vulnerability by sending renegotiation requests at a high rate. An successful exploit could increase the resource usage on the system, eventually leading to a DoS condition. This vulnerability affects version 2.1.

A vulnerability in the processing of IP Service Level Agreement (SLA) packets by Cisco IOS Software and Cisco IOS XE software could allow an unauthenticated, remote attacker to cause an interface wedge and an eventual denial of service (DoS) condition on the affected device. The vulnerability is due to improper socket resources handling in the IP SLA responder application code. An attacker could exploit this vulnerability by sending crafted IP SLA packets to an affected device. An exploit could allow the attacker to cause an interface to become wedged, resulting in an eventual denial of service (DoS) condition on the affected device.

A vulnerability in the ISDN functions of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect processing of specific values in the Q.931 information elements. An attacker could exploit this vulnerability by calling the affected device with specific Q.931 information elements being present. An exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition on an affected device.

A vulnerability in the Network-Based Application Recognition (NBAR) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability are due to a parsing issue on DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through routers that are running an affected version and have NBAR enabled. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

Cisco Unified SIP 3905 phones allow remote attackers to cause a denial of service (resource consumption and functionality loss) via a large amount of network traffic, aka Bug ID CSCuh51331.

A vulnerability in the Network-Based Application Recognition (NBAR) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability is due to a parsing issue on DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through routers that are running an affected version and have NBAR enabled. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the Network-Based Application Recognition (NBAR) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability is due to a parsing issue on DNS packets. An attacker could exploit these vulnerabilities by sending crafted DNS packets through routers that are running an affected version and have NBAR enabled. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 7800 Series and Cisco IP Phone 8800 Series could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code. The vulnerability exists because the software improperly validates user-supplied input during user authentication. An attacker could exploit this vulnerability by connecting to an affected device using HTTP and supplying malicious user credentials. A successful exploit could allow the attacker to trigger a reload of an affected device, resulting in a DoS condition, or to execute arbitrary code with the privileges of the app user. Cisco fixed this vulnerability in the following SIP Software releases: 10.3(1)SR5 and later for Cisco Unified IP Conference Phone 8831; 11.0(4)SR3 and later for Cisco Wireless IP Phone 8821 and 8821-EX; and 12.5(1)SR1 and later for the rest of the Cisco IP Phone 7800 Series and 8800 Series.

A vulnerability in the TCP processing engine of 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 reload, resulting in a denial of service (DoS) condition. The vulnerability is due to the improper handling of TCP traffic. An attacker could exploit this vulnerability by sending a specific sequence of packets at a high rate through an affected device. A successful exploit could allow the attacker to temporarily disrupt traffic through the device while it reboots.

Cisco AsyncOS before 8.5.7-042, 9.x before 9.1.0-032, 9.1.x before 9.1.1-023, and 9.5.x and 9.6.x before 9.6.0-042 on Email Security Appliance (ESA) devices; before 9.1.0-032, 9.1.1 before 9.1.1-005, and 9.5.x before 9.5.0-025 on Content Security Management Appliance (SMA) devices; and before 7.7.0-725 and 8.x before 8.0.8-113 on Web Security Appliance (WSA) devices allows remote attackers to cause a denial of service (memory consumption) via a flood of TCP packets, aka Bug IDs CSCus79774, CSCus79777, and CSCzv95795.

Multiple vulnerabilities in the Server Message Block (SMB) Protocol preprocessor detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, adjacent or remote attacker to cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the Protocol Independent Multicast (PIM) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause the PIM process to restart, resulting in a denial of service condition on an affected device. The vulnerability is due to the incorrect processing of crafted AutoRP packets. An attacker could exploit this vulnerability by sending crafted packets to port UDP 496 on a reachable IP address on the device. A successful exploit could allow the attacker to cause the PIM process to restart. Software versions prior to 6.2.3, 6.3.2, 6.4.0, and 6.5.1 are affected.

A vulnerability in the User Data Services (UDS) API of Cisco Unified Communications Manager (Unified CM) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the management GUI. The vulnerability is due to improper validation of input parameters in the UDS API requests. An attacker could exploit this vulnerability by sending a crafted request to the UDS API of an affected device. A successful exploit could allow the attacker to make the A Cisco DB service quit unexpectedly, preventing admin access to the Unified CM management GUI. Manual intervention may be required to restore normal operation. Software versions 10.5, 11.5, 12.0, 12.5 are affected.

A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 8800 Series could allow an unauthenticated, remote attacker to bypass authorization, access critical services, and cause a denial of service (DoS) condition. The vulnerability exists because the software fails to sanitize URLs before it handles requests. An attacker could exploit this vulnerability by submitting a crafted URL. A successful exploit could allow the attacker to gain unauthorized access to critical services and cause a DoS condition. This vulnerability affects Cisco IP Phone 8800 Series products running a SIP Software release prior to 11.0(5) for Wireless IP Phone 8821 and 8821-EX; and 12.5(1)SR1 for the IP Conference Phone 8832 and the rest of the IP Phone 8800 Series. Cisco IP Conference Phone 8831 is not affected.

A vulnerability in the Internet Key Exchange Version 2 Mobility and Multihoming Protocol (MOBIKE) feature for the Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a memory leak or a reload of an affected device that leads to a denial of service (DoS) condition. The vulnerability is due to the incorrect processing of certain MOBIKE packets. An attacker could exploit this vulnerability by sending crafted MOBIKE packets to an affected device to be processed. A successful exploit could cause an affected device to continuously consume memory and eventually reload, resulting in a DoS condition. The MOBIKE feature is supported only for IPv4 addresses.

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.

A vulnerability in the internal packet-processing functionality of Cisco Firepower Threat Defense (FTD) Software for the Cisco Firepower 2100 Series could allow an unauthenticated, remote attacker to cause an affected device to stop processing traffic, resulting in a denial of service (DoS) condition. The vulnerability is due to a logic error, which may prevent ingress buffers from being replenished under specific traffic conditions. An attacker could exploit this vulnerability by sending a series of crafted packets to an affected device. A successful exploit could allow the attacker to consume all input buffers, which are shared between all interfaces, leading to a queue wedge condition in all active interfaces. This situation would cause an affected device to stop processing any incoming traffic and result in a DoS condition until the device is reloaded manually.

Multiple vulnerabilities in the Server Message Block (SMB) Protocol preprocessor detection engine for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, adjacent or remote attacker to cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

Memory leak in the Certificate Trust List (CTL) Provider service in Cisco Unified Communications Manager (CUCM) 5.x before 5.1(3) allows remote attackers to cause a denial of service (memory consumption and service interruption) via a series of malformed TCP packets, as demonstrated by TCPFUZZ, aka Bug ID CSCsj80609.

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 the affected device. The vulnerability is due to an issue with allocating and freeing memory buffers in the network stack. An attacker could exploit this vulnerability by sending crafted TCP streams to an affected device in a sustained way. A successful exploit could cause the network stack of an affected device to run out of available buffers, impairing operations of control plane and management plane protocols, resulting in a DoS condition. Note: This vulnerability can be triggered only by traffic that is destined to an affected device and cannot be exploited using traffic that transits an affected device. Nexus 1000V Switch for Microsoft Hyper-V is affected in versions prior to 5.2(1)SM3(2.1). Nexus 1000V Switch for VMware vSphere is affected in versions prior to 5.2(1)SV3(4.1a). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(6) and 9.2(2). Nexus 3500 Platform Switches are affected in versions prior to 6.0(2)A8(11), 7.0(3)I7(6), and 9.2(2). Nexus 3600 Platform Switches are affected in versions prior to 7.0(3)F3(5) and 9.2(2). Nexus 5500, 5600, and 6000 Series Switches are affected in versions prior to 7.1(5)N1(1b) and 7.3(5)N1(1). Nexus 7000 and 7700 Series Switches are affected in versions prior to 6.2(22. Nexus 9500 R-Series Line Cards and Fabric Modules are affected in versions prior to 7.0(3)F3(5) and 9.2(2). UCS 6200 and 6300 Series Fabric Interconnect are affected in versions prior to 3.2(3j) and 4.0(2a). UCS 6400 Series Fabric Interconnect are affected in versions prior to 4.0(2a).

Multiple vulnerabilities in the implementation of the Lightweight Directory Access Protocol (LDAP) feature in Cisco FXOS Software and Cisco NX-OS 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 by an affected device. An attacker could exploit these vulnerabilities by sending an LDAP packet crafted using Basic Encoding Rules (BER) to an affected device. The LDAP packet must have a source IP address of an LDAP server configured on the targeted device. A successful exploit could cause the affected device to reload, resulting in a DoS condition. Firepower 4100 Series Next-Generation Firewalls are affected in versions prior to 2.0.1.201, 2.2.2.54, and 2.3.1.75. Firepower 9300 Security Appliances are affected in versions prior to 2.0.1.201, 2.2.2.54 and 2.3.1.75. MDS 9000 Series Multilayer Switches are affected in versions prior to 8.2(1). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(1). Nexus 3500 Platform Switches are affected in versions prior to 7.0(3)I7(2). Nexus 7000 and 7700 Series Switches are affected in versions prior to 8.2(1). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected in versions prior to 7.0(3)I7(1). Cisco UCS 6200 and 6300 Fabric Interconnect devices are affected in versions prior to 3.2(2b).

Multiple vulnerabilities in the implementation of the Lightweight Directory Access Protocol (LDAP) feature in Cisco FXOS Software and Cisco NX-OS 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 by an affected device. An attacker could exploit these vulnerabilities by sending an LDAP packet crafted using Basic Encoding Rules (BER) to an affected device. The LDAP packet must have a source IP address of an LDAP server configured on the targeted device. A successful exploit could cause the affected device to reload, resulting in a DoS condition. Firepower 4100 Series Next-Generation Firewalls are affected in versions prior to 2.0.1.201, 2.2.2.54, and 2.3.1.75. Firepower 9300 Security Appliances are affected in versions prior to 2.0.1.201, 2.2.2.54, and 2.3.1.75. MDS 9000 Series Multilayer Switches are affected in versions prior to 8.2(1). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(1). Nexus 3500 Platform Switches are affected in versions prior to 7.0(3)I7(2). Nexus 7000 and 7700 Series Switches are affected in versions prior to 6.2(20), 7.3(2)D1(1), and 8.2(1). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected in versions prior to 7.0(3)I7(1). UCS 6200 and 6300 Fabric Interconnect are affected in versions prior to 3.2(2b).

A vulnerability in the Cisco Fabric Services component of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a buffer overflow, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of Cisco Fabric Services packets. An attacker could exploit this vulnerability by sending a crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to cause a buffer overflow, resulting in process crashes and a DoS condition on the device. MDS 9000 Series Multilayer Switches are affected running software versions prior to 6.2(25), 8.1(1b), 8.3(1). Nexus 3000 Series Switches are affected running software versions prior to 7.0(3)I4(9) and 7.0(3)I7(4). Nexus 3500 Platform Switches are affected running software versions prior to 6.0(2)A8(10) and 7.0(3)I7(4). Nexus 3600 Platform Switches are affected running software versions prior to 7.0(3)F3(5) Nexus 7000 and 7700 Series Switches are affected running software versions prior to 6.2(22) and 8.2(3). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected running software versions prior to 7.0(3)I4(9) and 7.0(3)I7(4). Nexus 9500 R-Series Line Cards and Fabric Modules are affected running software versions prior to 7.0(3)F3(5). UCS 6200, 6300, and 6400 Fabric Interconnects are affected running software versions prior to 3.2(3j) and 4.0(2a).

A vulnerability in the UDP protocol implementation for Cisco IoT Field Network Director (IoT-FND) could allow an unauthenticated, remote attacker to exhaust system resources, resulting in a denial of service (DoS) condition. The vulnerability is due to improper resource management for UDP ingress packets. An attacker could exploit this vulnerability by sending a high rate of UDP packets to an affected system within a short period of time. A successful exploit could allow the attacker to exhaust available system resources, resulting in a DoS condition.

A vulnerability in the default configuration of the Cisco Aironet Active Sensor could allow an unauthenticated, remote attacker to restart the sensor. The vulnerability is due to a default local account with a static password. The account has privileges only to reboot the device. An attacker could exploit this vulnerability by guessing the account name and password to access the CLI. A successful exploit could allow the attacker to reboot the device repeatedly, creating a denial of service (DoS) condition. It is not possible to change the configuration or view sensitive data with this account. Versions prior to DNAC1.2.8 are affected.

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.

A vulnerability in the call-handling functionality of Session Initiation Protocol (SIP) Software for Cisco IP Phone 7800 Series and 8800 Series could allow an unauthenticated, remote attacker to cause an affected phone to reload unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability is due to incomplete error handling when XML data within a SIP packet is parsed. An attacker could exploit this vulnerability by sending a SIP packet that contains a malicious XML payload to an affected phone. A successful exploit could allow the attacker to cause the affected phone to reload unexpectedly, resulting in a temporary DoS condition.

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 trigger a reload of an affected device, resulting in 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. The attacker does not need valid credentials to authenticate the VPN session, nor does the attacker's source address need to match a peer statement in the crypto map applied to the ingress interface of the affected device. An exploit could allow the attacker to exhaust system memory resources, leading to a reload of an affected device.

Multiple vulnerabilities in the ingress packet processing function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Unspecified vulnerability in the SSH server in (1) Cisco Service Control Engine (SCE) 3.0.x before 3.0.7 and 3.1.x before 3.1.0, and (2) Icon Labs Iconfidant SSH before 2.3.8, allows remote attackers to cause a denial of service (management interface outage) via SSH traffic that occurs during management operations and triggers "illegal I/O operations," aka Bug ID CSCsh49563.

Multiple vulnerabilities in Cisco SD-WAN vManage Software could allow an unauthenticated, remote attacker to execute arbitrary code or gain access to sensitive information, or allow an authenticated, local attacker to gain escalated privileges or gain unauthorized access to the application. For more information about these vulnerabilities, see the Details section of this advisory.

Multiple vulnerabilities in Cisco SD-WAN products could allow an unauthenticated, remote attacker to execute denial of service (DoS) attacks against an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

The HTTP server in Cisco Unified IP Phone 7935 and 7936 running SCCP firmware allows remote attackers to cause a denial of service (reboot) via a crafted HTTP request.

Cisco Adaptive Security Appliances (ASA) 5500 series devices with software before 8.2(3) do not properly handle Online Certificate Status Protocol (OCSP) connection failures, which allows remote OCSP responders to cause a denial of service (TCP socket exhaustion) by rejecting connection attempts, aka Bug ID CSCsz36816.

A vulnerability in the Secure Shell (SSH) session management for Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the SSH process is not properly deleted when an SSH connection to the device is disconnected. An attacker could exploit this vulnerability by repeatedly opening SSH connections to an affected device. A successful exploit could allow the attacker to exhaust system resources by initiating multiple SSH connections to the device that are not effectively terminated, which could result in a DoS condition.

Multiple vulnerabilities in Cisco SD-WAN products could allow an unauthenticated, remote attacker to execute denial of service (DoS) attacks against an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the vDaemon process of Cisco SD-WAN Software could allow an unauthenticated, remote attacker to cause a device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient handling of malformed packets. An attacker could exploit this vulnerability by sending crafted traffic 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 Point-to-Point Tunneling Protocol (PPTP) VPN packet processing functionality in Cisco Aironet Access Points (APs) could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of Generic Routing Encapsulation (GRE) frames that pass through the data plane of an affected AP. An attacker could exploit this vulnerability by associating to a vulnerable AP, initiating a PPTP VPN connection to an arbitrary PPTP VPN server, and sending a malicious GRE frame through the data plane of the AP. A successful exploit could allow the attacker to cause an internal process of the targeted AP to crash, which in turn would cause the AP to reload. The AP reload would cause a DoS condition for clients that are associated with the AP.

A vulnerability in the software-based SSL/TLS message handler of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of SSL/TLS messages when the device performs software-based SSL decryption. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message through an affected device. SSL/TLS messages sent to an affected device do not trigger this vulnerability. A successful exploit could allow the attacker to cause a process to crash. This crash would then trigger a reload of the device. No manual intervention is needed to recover the device after the reload.

Cisco Aironet 1800 devices with software 8.1(131.0) allow remote attackers to cause a denial of service (CPU consumption) by improperly establishing many SSHv2 connections, aka Bug ID CSCux13374.

Unspecified vulnerability on Cisco Adaptive Security Appliances (ASA) 5500 series devices with software before 8.3(2) allows remote attackers to cause a denial of service (device crash) via a large number of LAN-to-LAN (aka L2L) IPsec sessions, aka Bug ID CSCth36592.