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.

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 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.

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 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.

Cisco Adaptive Security Appliance (ASA) Software 8.2.x before 8.2(5.46), 8.3.x before 8.3(2.39), 8.4.x before 8.4(7), 8.5.x before 8.5(1.18), 8.6.x before 8.6(1.12), 8.7.x before 8.7(1.7), 9.0.x before 9.0(3.3), and 9.1.x before 9.1(1.8), when the DNS ALPI engine is enabled for TCP, allows remote attackers to cause a denial of service (device reload) via crafted TCP DNS packets, aka Bug ID CSCug03975.

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.

A vulnerability in the implementation of Common Industrial Protocol (CIP) functionality in Cisco Industrial Ethernet 2000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to a system memory leak. More Information: CSCvc54788. Known Affected Releases: 15.2(5.4.32i)E2. Known Fixed Releases: 15.2(5.4.62i)E2.

The IPsec implementation in Cisco Adaptive Security Appliance (ASA) Software 9.1 before 9.1(1.7), when an IPsec VPN tunnel is enabled, allows remote attackers to cause a denial of service (device reload) via a (1) ICMP or (2) ICMPv6 packet that is improperly handled during decryption, aka Bug ID CSCue18975.

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.

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.

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 with software 7.x before 7.2(5.10), 8.0 before 8.0(5.31), 8.1 and 8.2 before 8.2(5.38), 8.3 before 8.3(2.37), 8.4 before 8.4(5), 8.5 before 8.5(1.17), 8.6 before 8.6(1.10), and 8.7 before 8.7(1.3) allow remote attackers to cause a denial of service (device reload) via a crafted certificate, aka Bug ID CSCuc72408.

The RSVP protocol implementation in Cisco IOS 12.2 and 15.0 through 15.2 and IOS XE 3.1.xS through 3.4.xS before 3.4.5S and 3.5.xS through 3.7.xS before 3.7.2S, when MPLS-TE is enabled, allows remote attackers to cause a denial of service (incorrect memory access and device reload) via a traffic engineering PATH message in an RSVP packet, aka Bug ID CSCtg39957.

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.

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.

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 AAA functionality in the IPv4 SSL VPN implementations on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.2 before 8.2(5.30) and 8.3 before 8.3(2.34) allows remote attackers to cause a denial of service (device reload) via a crafted authentication response, aka Bug ID CSCtz04566.

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.

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 CSCtr21346 and CSCtr27521.

The BGP implementation in Cisco IOS 15.2, IOS XE 3.5.xS before 3.5.2S, and IOS XR 4.1.0 through 4.2.2 allows remote attackers to cause a denial of service (multiple connection resets) by leveraging a peer relationship and sending a malformed attribute, aka Bug IDs CSCtt35379, CSCty58300, CSCtz63248, and CSCtz62914.

Cisco Unified Wireless Network (UWN) Solution 7.x before 7.0.98.0 allows remote attackers to cause a denial of service (device crash) by pinging a virtual interface, aka Bug ID CSCte55370.

Unspecified vulnerability in Stack Group Bidding Protocol (SGBP) support in Cisco IOS 12.0 through 12.4 running on various Cisco products, when SGBP is enabled, allows remote attackers on the local network to cause a denial of service (device hang and network traffic loss) via a crafted UDP packet to port 9900.

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.

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.

A vulnerability in the processing of SSH connections for multi-instance deployments of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. This vulnerability is due to a lack of proper error handling when an SSH session fails to be established. An attacker could exploit this vulnerability by sending a high rate of crafted SSH connections to the instance. A successful exploit could allow the attacker to cause resource exhaustion, which causes a DoS condition on the affected device. The device must be manually reloaded to recover.

Secure Shell (SSH) 2 in Cisco IOS 12.0 through 12.3 allows remote attackers to cause a denial of service (device reload) (1) via a username that contains a domain name when using a TACACS+ server to authenticate, (2) when a new SSH session is in the login phase and a currently logged in user issues a send command, or (3) when IOS is logging messages and an SSH session is terminated while the server is sending data.

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.

Memory leak in Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 6.x before 6.1(5)su3, 7.x before 7.1(5b)su3, 8.0 before 8.0(3a)su2, and 8.5 before 8.5(1) allows remote attackers to cause a denial of service (memory consumption and process failure) via a malformed SIP message, aka Bug ID CSCti42904.

Cisco IOS before 15.0(1)XA1, when certain TFTP debugging is enabled, allows remote attackers to cause a denial of service (device crash) via a TFTP copy over IPv6, aka Bug ID CSCtb28877.

Buffer overflow in the embedded HTTP server for Cisco Catalyst switches running CatOS 5.4 through 7.3 allows remote attackers to cause a denial of service (reset) via a long HTTP request.

Unspecified vulnerability on the Cisco Firewall Services Module (FWSM) with software 3.2 before 3.2(17.2), 4.0 before 4.0(11.1), and 4.1 before 4.1(1.2) for Catalyst 6500 series switches and 7600 series routers, when multi-mode is enabled, allows remote attackers to cause a denial of service (device reload) via crafted (1) Telnet, (2) SSH, or (3) ASDM traffic over TCP, aka Bug ID CSCtg68694.

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 IGMPv3 implementation in Cisco IOS 12.2, 12.3, 12.4, and 15.0 and IOS XE 2.5.x before 2.5.2, when PIM is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed IGMP packet, aka Bug ID CSCte14603.

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.

Heap-based buffer overflow in the TFTP server capability in Cisco IOS 11.1, 11.2, and 11.3 allows remote attackers to cause a denial of service (reset) or modify configuration via a long filename.

Cisco IOS 12.2 through 12.4, when certain PMTUD, SNAT, or window-size configurations are used, allows remote attackers to cause a denial of service (infinite loop, and device reload or hang) via a TCP segment with crafted options, aka Bug ID CSCsz75186.

Unspecified vulnerability in Cisco ASA 5500 Series Adaptive Security Appliance 7.0 before 7.0(8.10), 7.2 before 7.2(4.45), 8.0 before 8.0(4.44), 8.1 before 8.1(2.35), and 8.2 before 8.2(1.10) allows remote attackers to cause a denial of service (device reload) via a malformed TCP segment when certain NAT translation and Cisco AIP-SSM configurations are used, aka Bug ID CSCtb37219.

Cisco VPN 3000 series concentrators before 2.5.2(F) allow remote attackers to cause a denial of service via a flood of invalid login requests to (1) the SSL service, or (2) the telnet service, which do not properly disconnect the user after several failed login attempts.

The IOS HTTP service in Cisco routers and switches running IOS 11.1 through 12.1 allows remote attackers to cause a denial of service by requesting a URL that contains a %% string.

A vulnerability in the Border Gateway Protocol (BGP) over an Ethernet Virtual Private Network (EVPN) for Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload, resulting in a denial of service (DoS) condition, or potentially corrupt the BGP routing table, which could result in network instability. The vulnerability exists due to changes in the implementation of the BGP MPLS-Based Ethernet VPN RFC (RFC 7432) draft between IOS XE software releases. When the BGP Inclusive Multicast Ethernet Tag Route or BGP EVPN MAC/IP Advertisement Route update packet is received, it could be possible that the IP address length field is miscalculated. An attacker could exploit this vulnerability by sending a crafted BGP packet to an affected device after the BGP session was established. An exploit could allow the attacker to cause the affected device to reload or corrupt the BGP routing table; either outcome would result in a DoS. The vulnerability may be triggered when the router receives a crafted BGP message from a peer on an existing BGP session. This vulnerability affects all releases of Cisco IOS XE Software prior to software release 16.3 that support BGP EVPN configurations. If the device is not configured for EVPN, it is not vulnerable. Cisco Bug IDs: CSCui67191, CSCvg52875.

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.

Cisco IOS 12.0 through 12.4, when IP-based tunnels and the Cisco Express Forwarding feature are enabled, allows remote attackers to cause a denial of service (device reload) via malformed packets, aka Bug ID CSCsx70889.

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.

Cisco IOS 12.1, 12.2, 12.3, and 12.4, with IPv4 UDP services and the IPv6 protocol enabled, allows remote attackers to cause a denial of service (device crash and possible blocked interface) via a crafted IPv6 packet to the device.

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.

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 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.

Memory leak in Secure Shell (SSH) in Cisco IOS 12.0 through 12.3, when authenticating against a TACACS+ server, allows remote attackers to cause a denial of service (memory consumption) via an incorrect username or password.