A vulnerability in the IPv6 Simple Network Management Protocol (SNMP) code of Cisco IOS and Cisco IOS XE Software could allow an authenticated, remote attacker to cause high CPU usage or a reload of the device. The vulnerability is due to IPv6 sub block corruption. An attacker could exploit this vulnerability by polling the affected device IPv6 information. An exploit could allow the attacker to trigger high CPU usage or a reload of the device. Known Affected Releases: Denali-16.3.1. Cisco Bug IDs: CSCvb14640.

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.

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

Memory leak in the crypto functionality in Cisco Adaptive Security Appliance (ASA) 5500 devices 7.2 before 7.2(4)2, 8.0 before 8.0(3)14, and 8.1 before 8.1(1)4, when configured as a clientless SSL VPN endpoint, allows remote attackers to cause a denial of service (memory consumption and VPN hang) via a crafted SSL or HTTP packet, aka Bug ID CSCso66472.

A vulnerability in the detection engine parsing of Pragmatic General Multicast (PGM) protocol packets for Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to the Snort process unexpectedly restarting. The vulnerability is due to improper input validation of the fields in the PGM protocol packet. An attacker could exploit this vulnerability by sending a crafted PGM packet to the detection engine on the targeted device. An exploit could allow the attacker to cause a DoS condition if the Snort process restarts and traffic inspection is bypassed or traffic is dropped. This vulnerability affects Cisco Firepower System Software that has one or more file action policies configured and is running on any of the following Cisco products: Adaptive Security Appliance (ASA) 5500-X Series with FirePOWER Services; Adaptive Security Appliance (ASA) 5500-X Series Next-Generation Firewalls; Advanced Malware Protection (AMP) for Networks, 7000 Series Appliances; Advanced Malware Protection (AMP) for Networks, 8000 Series Appliances; Firepower 4100 Series Security Appliances; FirePOWER 7000 Series Appliances; FirePOWER 8000 Series Appliances; Firepower 9300 Series Security Appliances; FirePOWER Threat Defense for Integrated Services Routers (ISRs); Industrial Security Appliance 3000; Sourcefire 3D System Appliances; Virtual Next-Generation Intrusion Prevention System (NGIPSv) for VMware. Fixed versions: 5.4.0.10 5.4.1.9 6.0.1.3 6.1.0 6.2.0. Cisco Bug IDs: CSCuz00876.

Cisco Secure ACS 3.x before 3.3(4) Build 12 patch 7, 4.0.x, 4.1.x before 4.1(4) Build 13 Patch 11, and 4.2.x before 4.2(0) Build 124 Patch 4 does not properly handle an EAP Response packet in which the value of the length field exceeds the actual packet length, which allows remote authenticated users to cause a denial of service (CSRadius and CSAuth service crash) or possibly execute arbitrary code via a crafted RADIUS (1) EAP-Response/Identity, (2) EAP-Response/MD5, or (3) EAP-Response/TLS Message Attribute packet.

A vulnerability in the interaction between the TCP Intercept feature and the Snort 3 detection engine on Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured policies on an affected system. Devices that are configured with Snort 2 are not affected by this vulnerability. This vulnerability is due to a logic error when handling embryonic (half-open) TCP connections. An attacker could exploit this vulnerability by sending a crafted traffic pattern through an affected device. A successful exploit could allow unintended traffic to enter the network protected by the affected device.

A vulnerability in the implementation of the IPv4 fragmentation reassembly code in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper management of resources during fragment reassembly. An attacker could exploit this vulnerability by sending specific sizes of fragmented packets to an affected device or through a Virtual Fragmentation Reassembly (VFR)-enabled interface on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Note: This vulnerability affects Cisco ASR 1000 Series Aggregation Services Routers and Cisco cBR-8 Converged Broadband Routers if they are running Cisco IOS XE Software Release 17.12.1 or 17.12.1a.

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.

Cisco Adaptive Security Appliance (ASA) and Cisco PIX security appliance 7.2.x before 7.2(3)2 and 8.0.x before 8.0(2)17 allows remote attackers to cause a denial of service (device reload) via a port scan against TCP port 443 on the device.

Memory leak in the Certificate Trust List (CTL) Provider service in Cisco Unified Communications Manager (CUCM) 5.x before 5.1(3) and 6.x before 6.1(1) allows remote attackers to cause a denial of service (memory consumption and service interruption) via a series of malformed TCP packets, aka Bug ID CSCsi98433.

The data-link switching (DLSw) component in Cisco IOS 12.0 through 12.4 allows remote attackers to cause a denial of service (device restart or memory consumption) via crafted (1) UDP port 2067 or (2) IP protocol 91 packets.

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.

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.

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.

A vulnerability in the TCP stack of Cisco SocialMiner could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition in the notification system. The vulnerability is due to faulty handling of new TCP connections to the affected application. An attacker could exploit this vulnerability by sending a malicious TCP packet to the vulnerable service. An exploit could allow the attacker to create a DoS condition by interrupting certain phone services. A manual restart of the service may be required to restore full functionalities. Cisco Bug IDs: CSCvh48368.

Cisco Systems VPN Client IPSec Driver (CVPNDRVA.sys) 5.0.02.0090 allows local users to cause a denial of service (crash) by calling the 0x80002038 IOCTL with a small size value, which triggers memory corruption.

A vulnerability in the identity-based firewall (IDFW) rule processing feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass security protections. This vulnerability is due to improper handling of network requests by affected devices configured to use object group search. An attacker could exploit this vulnerability by sending a specially crafted network request to an affected device. A successful exploit could allow the attacker to bypass access control list (ACL) rules on the device, bypass security protections, and send network traffic to unauthorized hosts.

Unspecified vulnerability in SSHield 1.6.1 with OpenSSH 3.0.2p1 on Cisco WebNS 8.20.0.1 on Cisco Content Services Switch (CSS) series 11000 devices allows remote attackers to cause a denial of service (connection slot exhaustion and device crash) via a series of large packets designed to exploit the SSH CRC32 attack detection overflow (CVE-2001-0144), possibly a related issue to CVE-2002-1024.

Cisco Wireless LAN Controller (WLC) before 3.2.116.21, and 4.0.x before 4.0.155.0, allows remote attackers on a local network to cause a denial of service (device crash) via malformed Ethernet traffic.

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 Network Processing Unit (NPU) in the Cisco Wireless LAN Controller (WLC) before 3.2.171.5, 4.0.x before 4.0.206.0, and 4.1.x allows remote attackers on a local wireless network to cause a denial of service (loss of packet forwarding) via (1) crafted SNAP packets, (2) malformed 802.11 traffic, or (3) packets with certain header length values, aka Bug IDs CSCsg15901 and CSCsh10841.

A vulnerability in the handling of IP fragments for the Cisco Small Business SPA300, SPA500, and SPA51x Series IP Phones could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to the inability to handle many large IP fragments for reassembly in a short duration. An attacker could exploit this vulnerability by sending a crafted stream of IP fragments to the targeted device. An exploit could allow the attacker to cause a DoS condition when the device unexpectedly reloads. Cisco Bug IDs: CSCve82586.

A vulnerability in the DNS input packet processor for Cisco Prime Network Registrar could allow an unauthenticated, remote attacker to cause the DNS process to momentarily restart, which could lead to a partial denial of service (DoS) condition on the affected system. The vulnerability is due to incomplete DNS packet header validation when the packet is received by the application. An attacker could exploit this vulnerability by sending a malformed DNS packet to the application. An exploit could allow the attacker to cause the DNS process to restart, which could lead to a DoS condition. This vulnerability affects Cisco Prime Network Registrar on all software versions prior to 8.3.5. Cisco Bug IDs: CSCvb55412.

A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system as the root user. This vulnerability is due to incorrect handling of certain crafted software images that are uploaded to the affected device. An attacker could exploit this vulnerability by authenticating to the system as an administrative user and then uploading specific crafted software images to the affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system as the root user.

A vulnerability in the ingress packet processing function of Cisco IOS Software for Cisco Catalyst 4000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource allocation when processing TCP packets directed to the device on specific Cisco Catalyst 4000 Series Switches. An attacker could exploit this vulnerability by sending crafted TCP streams to an affected device. A successful exploit could cause the affected device to run out of buffer resources, impairing operations of control plane and management plane protocols, resulting in a DoS condition. 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.

A vulnerability in the Secure Sockets Layer (SSL) VPN feature of Cisco Adaptive Security Appliance (ASA) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition that prevents the creation of new SSL/Transport Layer Security (TLS) connections to an affected device. The vulnerability is due to incorrect handling of Base64-encoded strings. An attacker could exploit this vulnerability by opening many SSL VPN sessions to an affected device. The attacker would need to have valid user credentials on the affected device to exploit this vulnerability. A successful exploit could allow the attacker to overwrite a special system memory location, which will eventually result in memory allocation errors for new SSL/TLS sessions to the device, preventing successful establishment of these sessions. A reload of the device is required to recover from this condition. Established SSL/TLS connections to the device and SSL/TLS connections through the device are not affected. Note: Although this vulnerability is in the SSL VPN feature, successful exploitation of this vulnerability would affect all new SSL/TLS sessions to the device, including management sessions.

A vulnerability in the Simple Network Management Protocol (SNMP) punt handling function of Cisco cBR-8 Converged Broadband Routers could allow an authenticated, remote attacker to overload a device punt path, resulting in a denial of service (DoS) condition. This vulnerability is due to the punt path being overwhelmed by large quantities of SNMP requests. An attacker could exploit this vulnerability by sending a large number of SNMP requests to an affected device. A successful exploit could allow the attacker to overload the device punt path, resulting in a DoS condition.

A vulnerability in Ethernet over GRE (EoGRE) packet processing of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9800 Family Wireless Controller, Embedded Wireless Controller, and Embedded Wireless on Catalyst 9000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper processing of malformed EoGRE packets. An attacker could exploit this vulnerability by sending malicious packets to the affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the Layer 2 punt code of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a queue wedge on an interface that receives specific Layer 2 frames, resulting in a denial of service (DoS) condition. This vulnerability is due to improper handling of certain Layer 2 frames. An attacker could exploit this vulnerability by sending specific Layer 2 frames on the segment the router is connected to. A successful exploit could allow the attacker to cause a queue wedge on the interface, resulting in a DoS condition.

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.

Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for Mac, and Cisco Jabber for mobile platforms could allow an attacker to access sensitive information or cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in CLI management in Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to access the underlying operating system as the root user. This vulnerability is due to the way the software handles concurrent CLI sessions. An attacker could exploit this vulnerability by authenticating to the device as an administrative user and executing a sequence of commands. A successful exploit could allow the attacker to obtain access to the underlying operating system as the root user.

Multiple vulnerabilities in Cisco Jabber for Windows, Cisco Jabber for Mac, and Cisco Jabber for mobile platforms could allow an attacker to access sensitive information or cause a denial of service (DoS) condition. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in Address Resolution Protocol (ARP) management of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to prevent an affected device from resolving ARP entries for legitimate hosts on the connected subnets. This vulnerability exists because ARP entries are mismanaged. An attacker could exploit this vulnerability by continuously sending traffic that results in incomplete ARP entries. A successful exploit could allow the attacker to cause ARP requests on the device to be unsuccessful for legitimate hosts, resulting in a denial of service (DoS) condition.

A vulnerability in the Akamai Connect feature of Cisco Wide Area Application Services (WAAS) Appliances could allow an unauthenticated, remote attacker to cause a denial-of-service (DoS) condition on an affected device. The vulnerability is due to certain file-handling inefficiencies of the affected system. An attacker could exploit this vulnerability by directing client systems to access a corrupted file that the client systems cannot decompress correctly. A successful exploit could allow the attacker to cause the affected device to crash or hang unexpectedly and result in a DoS condition that may require manual intervention to regain normal operating conditions. Cisco Bug IDs: CSCve82472.

A vulnerability in the licensing service of Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.The vulnerability is due to improper handling of system resource values by the affected system. An attacker could exploit this vulnerability by sending malicious requests to the targeted system. A successful exploit could allow the attacker to cause the affected system to become unresponsive, resulting in a DoS condition and preventing the management of dependent devices.

A vulnerability in Cisco Aironet Series Access Points Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to the improper processing of client packets that are sent to an affected access point (AP). An attacker could exploit this vulnerability by sending a large number of sustained client packets to the affected AP. A successful exploit could allow the attacker to cause the affected AP to crash, resulting in a DoS condition.

A vulnerability in the ARP packet processing of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Security Appliances could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect processing of ARP packets received by the management interface of an affected device. An attacker could exploit this vulnerability by sending a series of unicast ARP packets in a short timeframe that would reach the management interface of an affected device. A successful exploit could allow the attacker to consume resources on an affected device, which would prevent the device from sending internal system keepalives and eventually cause the device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the Protocol Independent Multicast (PIM) feature for IPv6 networks (PIM6) 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 improper error handling when processing inbound PIM6 packets. An attacker could exploit this vulnerability by sending multiple crafted PIM6 packets to an affected device. A successful exploit could allow the attacker to cause the PIM6 application to leak system memory. Over time, this memory leak could cause the PIM6 application to stop processing legitimate PIM6 traffic, leading to a DoS condition on the affected device.

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 Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P) Software could allow an authenticated, remote attacker to cause the Cisco XCP Authentication Service on an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to improper handling of login requests. An attacker could exploit this vulnerability by sending a crafted client login request to an affected device. A successful exploit could allow the attacker to cause a process to crash, resulting in a DoS condition for new login attempts. Users who are authenticated at the time of the attack would not be affected. There are workarounds that address this vulnerability.

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 handling of Inter-Access Point Protocol (IAPP) messages by Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. The vulnerability exist because the software improperly validates input on fields within IAPP messages. An attacker could exploit the vulnerability by sending malicious IAPP messages to an affected device. A successful exploit could allow the attacker to cause the Cisco WLC Software to reload, resulting in a DoS condition. Software versions prior to 8.2.170.0, 8.5.150.0, and 8.8.100.0 are affected.

A vulnerability in the web interface of Cisco IoT Field Network Director could allow an unauthenticated, remote attacker to trigger high CPU usage, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of Transport Layer Security (TLS) renegotiation requests. An attacker could exploit this vulnerability by sending renegotiation requests at a high rate. A successful exploit could increase the resource usage on the system, eventually leading to a DoS condition.

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 Simple Network Management Protocol (SNMP) input packet processor of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause the SNMP application to leak system memory, which could cause an affected device to restart unexpectedly. The vulnerability is due to improper error handling when processing inbound SNMP packets. An attacker could exploit this vulnerability by sending multiple crafted SNMP packets to an affected device. A successful exploit could allow the attacker to cause the SNMP application to leak system memory because of an improperly handled error condition during packet processing. Over time, this memory leak could cause the SNMP application to restart multiple times, leading to a system-level restart and a denial of service (DoS) condition.

A vulnerability in the WebVPN service of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper management of authenticated sessions in the WebVPN portal. An attacker could exploit this vulnerability by authenticating with valid credentials and accessing a specific URL in the WebVPN portal. A successful exploit could allow the attacker to cause the device to reload, resulting in a temporary DoS condition.