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.

The auto-update implementation in Cisco Adaptive Security Appliance (ASA) Software 9.0.3.6 and earlier allows remote attackers to cause a denial of service (device reload) via crafted update data, aka Bug ID CSCui33308.

The SQL*Net inspection engine in Cisco Adaptive Security Appliance (ASA) Software 7.x before 7.2(5.12), 8.x before 8.2(5.44), 8.3.x before 8.3(2.39), 8.4.x before 8.4(6), 8.5.x before 8.5(1.18), 8.6.x before 8.6(1.12), 8.7.x before 8.7(1.6), 9.0.x before 9.0(2.10), and 9.1.x before 9.1(2) and Firewall Services Module (FWSM) 3.1.x and 3.2.x before 3.2(27) and 4.x before 4.1(14) allows remote attackers to cause a denial of service (device reload) via crafted segmented Transparent Network Substrate (TNS) packets, aka Bug ID CSCub98434.

The NTP implementation in Cisco IOS 12.0 through 12.4 and 15.0 through 15.1, and IOS XE 2.1 through 3.3, does not properly handle encapsulation of multicast NTP packets within MSDP SA messages, which allows remote attackers to cause a denial of service (device reload) by leveraging an MSDP peer relationship, aka Bug ID CSCuc81226.

The PPTP implementation in Cisco IOS 12.2 and 15.0 through 15.3, when NAT is used, allows remote attackers to cause a denial of service (device reload) via crafted TCP port-1723 packets, aka Bug ID CSCtq14817.

Cisco Adaptive Security Appliance (ASA) Software does not properly handle errors during the processing of DNS responses, which allows remote attackers to cause a denial of service (device reload) via a malformed response, aka Bug ID CSCuj28861.

The TCP implementation in Cisco IOS does not properly implement the transitions from the ESTABLISHED state to the CLOSED state, which allows remote attackers to cause a denial of service (flood of ACK packets) via a crafted series of ACK and FIN packets, aka Bug ID CSCtz14399.

Unspecified vulnerability in the Multi Protocol Label Switching (MPLS) Forwarding Infrastructure (MFI) in Cisco IOS 12.2 and 12.4 allows remote attackers to cause a denial of service (memory corruption) via crafted packets for which the software path is used.

The TLS/SSLv3 module on Cisco ONS 15454 controller cards allows remote attackers to cause a denial of service (card reset) via crafted (1) TLS or (2) SSLv3 packets, aka Bug ID CSCuh34787.

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.

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.

Cisco IOS 12.4, when IOS firewall Application Inspection Control (AIC) with HTTP Deep Packet Inspection is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed HTTP transit packet.

A vulnerability in the RESTCONF and NETCONF-YANG access control list (ACL) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect processing of the ACL that is tied to the RESTCONF or NETCONF-YANG feature. An attacker could exploit this vulnerability by accessing the device using RESTCONF or NETCONF-YANG. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

Cisco Unified Communications Manager (Unified CM) 8.5(x) and 8.6(x) before 8.6(2a)su3 and 9.x before 9.1(1) does not properly restrict the rate of SIP packets, which allows remote attackers to cause a denial of service (memory and CPU consumption, and service disruption) via a flood of UDP packets to port 5060, aka Bug ID CSCub35869.

Cisco Adaptive Security Appliances (ASA) devices, when SMP is used, do not properly process X.509 certificates, which allows remote attackers to cause a denial of service (device crash) via a large volume of (1) SSL or (2) TLS traffic, aka Bug ID CSCuh19462.

Unspecified vulnerability in the Session Initiation Protocol (SIP) implementation in Cisco IOS 12.2 through 12.4 and Unified Communications Manager 4.1 through 6.1, when VoIP is configured, allows remote attackers to cause a denial of service (device or process reload) via unspecified valid SIP messages, aka Cisco Bug ID CSCsu38644, a different vulnerability than CVE-2008-3801 and CVE-2008-3802.

Unspecified vulnerability in the Session Initiation Protocol (SIP) implementation in Cisco IOS 12.2 through 12.4, when VoIP is configured, allows remote attackers to cause a denial of service (device reload) via unspecified valid SIP messages, aka Cisco bug ID CSCsk42759, a different vulnerability than CVE-2008-3800 and CVE-2008-3801.

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.

The HTTP server in Cisco Adaptive Security Appliance (ASA) 5500 devices 8.0 before 8.0(3)15 and 8.1 before 8.1(1)5, when configured as a clientless SSL VPN endpoint, does not properly process URIs, which allows remote attackers to cause a denial of service (device reload) via a URI in a crafted SSL or HTTP packet, aka Bug ID CSCsq19369.

Cisco PIX and 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 client VPN endpoint, do not properly process IPSec client authentication, which allows remote attackers to cause a denial of service (device reload) via a crafted authentication attempt, aka Bug ID CSCso69942.

A vulnerability in the Forwarding Information Base (FIB) code of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, network attacker to cause a denial of service (DoS) condition. The vulnerability is due to a limitation in the way the FIB is internally representing recursive routes. An attacker could exploit this vulnerability by injecting routes into the routing protocol that have a specific recursive pattern. The attacker must be in a position on the network that provides the ability to inject a number of recursive routes with a specific pattern. An exploit could allow the attacker to cause an affected device to reload, creating a DoS condition. Cisco Bug IDs: CSCva91655.

The Location Bandwidth Manager (LBM) Intracluster-communication feature in Cisco Unified Communications Manager (CUCM) 9.x before 9.1(1) does not require authentication from the remote LBM Hub node, which allows remote attackers to conduct cache-poisoning attacks against transaction records, and cause a denial of service (bandwidth-pool consumption and call outage), via unspecified vectors, aka Bug ID CSCub28920.

Cisco IOS XE 3.2 through 3.4 before 3.4.2S, and 3.5, on 1000 series Aggregation Services Routers (ASR), when bridge domain interface (BDI) is enabled, allows remote attackers to cause a denial of service (card reload) via packets that are not properly handled during the processing of encapsulation, aka Bug ID CSCtt11558.

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.

Cisco Prime Central for Hosted Collaboration Solution (HCS) Assurance 8.6 and 9.0 allows remote attackers to cause a denial of service (CPU consumption and monitoring outage) via malformed TLS messages to TCP port (1) 9043 or (2) 9443, aka Bug ID CSCuc07155.

The DSP card on Cisco TelePresence MCU 4500 and 4501 devices before 4.3(2.30), TelePresence MCU MSE 8510 devices before 4.3(2.30), and TelePresence Server before 2.3(1.55) does not properly validate H.264 data, which allows remote attackers to cause a denial of service (device reload) via crafted RTP packets in a (1) SIP session or (2) H.323 session, aka Bug IDs CSCuc11328 and CSCub05448.

A vulnerability in the Session Initiation Protocol (SIP) on the Cisco TelePresence Video Communication Server (VCS) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the targeted appliance. The vulnerability is due to excessive SIP traffic sent to the device. An attacker could exploit this vulnerability by transmitting large volumes of SIP traffic to the VCS. An exploit could allow the attacker to cause a complete DoS condition on the targeted system. Cisco Bug IDs: CSCve32897.

Multiple Cisco products are affected by a vulnerability in Snort rules 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 handling of the Block with Reset or Interactive Block with Reset actions if a rule is configured without proper constraints. An attacker could exploit this vulnerability by sending a crafted IP packet to the affected device. A successful exploit could allow the attacker to cause through traffic to be dropped. Note: Only products with Snort3 configured and either a rule with Block with Reset or Interactive Block with Reset actions configured are vulnerable. Products configured with Snort2 are not vulnerable.

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 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.

Cisco IOS XE 03.02.00.XO.15.0(2)XO on Catalyst 4500E series switches, when a Supervisor Engine 7L-E card is installed, allows remote attackers to cause a denial of service (card reload) via malformed packets that trigger uncorrected ECC error messages, aka Bug ID CSCty88456.

A vulnerability in the Autonomic Networking Infrastructure (ANI) feature of Cisco IOS Software (15.4 through 15.6) and Cisco IOS XE Software (3.7 through 3.18, and 16) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incomplete input validation on certain crafted packets. An attacker could exploit this vulnerability by sending a crafted IPv6 packet to a device that is running a Cisco IOS Software or Cisco IOS XE Software release that supports the ANI feature. A device must meet two conditions to be affected by this vulnerability: (1) the device must be running a version of Cisco IOS Software or Cisco IOS XE Software that supports ANI (regardless of whether ANI is configured); and (2) the device must have a reachable IPv6 interface. An exploit could allow the attacker to cause the affected device to reload. Cisco Bug IDs: CSCvc42729.

The Intrusion Prevention System (IPS) feature in Cisco IOS 12.3 through 12.4 and 15.0 through 15.2, in certain configurations of enabled categories and missing signatures, allows remote attackers to cause a denial of service (device reload) via DNS packets, aka Bug ID CSCtw55976.

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and 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 input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a malicious HTTPS request to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

The DHCP server on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 7.0 before 7.2(5.8), 7.1 before 7.2(5.8), 7.2 before 7.2(5.8), 8.0 before 8.0(5.28), 8.1 before 8.1(2.56), 8.2 before 8.2(5.27), 8.3 before 8.3(2.31), 8.4 before 8.4(3.10), 8.5 before 8.5(1.9), and 8.6 before 8.6(1.5) does not properly allocate memory for DHCP packets, which allows remote attackers to cause a denial of service (device reload) via a series of crafted IPv4 packets, aka Bug ID CSCtw84068.

The DCERPC inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.3 before 8.3(2.25), 8.4 before 8.4(2.5), and 8.5 before 8.5(1.13) and the Firewall Services Module (FWSM) 4.1 before 4.1(7) in Cisco Catalyst 6500 series switches and 7600 series routers allows remote attackers to cause a denial of service (device reload) via a crafted DCERPC packet, aka Bug IDs CSCtr21376 and CSCtr27524.

Race condition in the Zone-Based Firewall in Cisco IOS 15.1 and 15.2, when IPS policies are configured, allows remote attackers to cause a denial of service (device crash) by sending IPv6 packets, aka Bug ID CSCtk53534.

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.

Cisco IOS 12.0 through 12.2, when supporting SSH, allows remote attackers to cause a denial of service (CPU consumption) via a large packet that was designed to exploit the SSH CRC32 attack detection overflow (CVE-2001-0144).

The SIP process in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 7.x before 7.1(5b)su4 and 8.x before 8.0(1) does not properly handle SDP data within a SIP call in certain situations related to use of the g729ar8 codec for a Media Termination Point (MTP), which allows remote attackers to cause a denial of service (service outage) via a crafted call, aka Bug ID CSCtc61990.

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.

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.

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.

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).