A vulnerability in the netconf interface of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on affected system. The vulnerability is due to improper handling of malformed requests processed by the netconf process. An attacker could exploit this vulnerability by sending malicious requests to the affected software. An exploit could allow the attacker to cause the targeted process to restart, resulting in a DoS condition on the affected system. Cisco Bug IDs: CSCvg95792.

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

A vulnerability in the Session Initiation Protocol (SIP) ingress packet processing of Cisco Unified IP Phone software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to a lack of flow-control mechanisms in the software. An attacker could exploit this vulnerability by sending high volumes of SIP INVITE traffic to the targeted device. Successful exploitation could allow the attacker to cause a disruption of services on the targeted IP phone. Cisco Bug IDs: CSCve10064, CSCve14617, CSCve14638, CSCve14683, CSCve20812, CSCve20926, CSCve20945.

A vulnerability in the file descriptor handling of Cisco TelePresence Video Communication Server (VCS) Expressway could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to exhaustion of file descriptors while processing a high volume of traffic. An attacker could exploit this vulnerability by establishing a high number of concurrent TCP connections to the vulnerable system. An exploit could allow the attacker to cause a restart in a specific process, resulting in a temporary interruption of service. Cisco Bug IDs: CSCvh77056, CSCvh77058, CSCvh95264.

A vulnerability in the IPsec Manager of Cisco StarOS for Cisco Aggregation Services Router (ASR) 5000 Series Routers and Virtualized Packet Core (VPC) System Software could allow an unauthenticated, remote attacker to terminate all active IPsec VPN tunnels and prevent new tunnels from being established, resulting in a denial of service (DoS) condition. The vulnerability is due to improper processing of corrupted Internet Key Exchange Version 2 (IKEv2) messages. An attacker could exploit this vulnerability by sending crafted IKEv2 messages toward an affected router. A successful exploit could allow the attacker to cause the ipsecmgr service to reload. A reload of this service could cause all IPsec VPN tunnels to be terminated and prevent new tunnels from being established until the service has restarted, resulting in a DoS condition. This vulnerability affects the following Cisco products when they are running Cisco StarOS: Cisco Aggregation Services Router (ASR) 5000 Series Routers, Virtualized Packet Core (VPC) System Software. Cisco Bug IDs: CSCve29605.

A vulnerability in the Real-Time Transport Protocol (RTP) bitstream processing of the Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient input validation of incoming RTP bitstreams. An attacker could exploit this vulnerability by sending a crafted RTP bitstream to an affected Cisco Meeting Server. A successful exploit could allow the attacker to deny audio and video services by causing media process crashes resulting in a DoS condition on the affected product. This vulnerability affects Cisco Meeting Server deployments that are running Cisco Meeting Server Software Releases 2.0, 2.1, 2.2, and 2.3. Cisco Bug IDs: CSCve79693, CSCvf91393, CSCvg64656, CSCvh30725, CSCvi86363.

A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol component of Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper input validation on fields within CAPWAP Discovery Request packets by the affected device. An attacker could exploit this vulnerability by sending malicious CAPWAP Discovery Request packets to the Cisco WLC Software. A successful exploit could allow the attacker to cause the Cisco WLC Software to disconnect associated access points (APs). While the APs disconnect and reconnect, service will be unavailable for a brief period of time, resulting in a DoS condition.

Cisco ACE A2(3.6) allows log retention DoS.

Memory leak in the SNMP process in Cisco IOS XR allows remote attackers to cause a denial of service (memory consumption or process reload) by sending many port-162 UDP packets, aka Bug ID CSCug80345.

The C-Series Rack Server component 1.4 in Cisco Unified Computing System (UCS) does not properly restrict inbound access to ports, which allows remote attackers to cause a denial of service (Integrated Management Controller reboot or hang) via crafted packets, as demonstrated by nmap, aka Bug ID CSCtx19850.

TMSSNMPService.exe in TelePresence Manager in Cisco TelePresence Management Suite (TMS) on 64-bit platforms allows remote attackers to cause a denial of service (process crash) via SNMP traps, aka Bug ID CSCue00028.

Cisco NX-OS on the Nexus 1000V does not assign the proper priority to heartbeat messages from a Virtual Ethernet Module (VEM) to a Virtual Supervisor Module (VSM), which allows remote attackers to cause a denial of service (false VEM unavailability report) via a flood of UDP packets, aka Bug ID CSCud14840.

Cisco Carrier Routing System (CRS) allows remote attackers to cause a denial of service (packet loss) via short malformed packets that trigger inefficient processing, aka Bug ID CSCud79136.

Cisco Tivoli Business Service Manager (TBSM) in Hosted Collaboration Mediation (HCM) in Cisco Hosted Collaboration Solution allows remote attackers to cause a denial of service (temporary service hang) by sending many TCP packets to certain ports, aka Bug ID CSCue03703.

Cisco Wireless LAN Controller (WLC) devices do not properly address the resource consumption of terminated TELNET sessions, which allows remote attackers to cause a denial of service (TELNET outage) by making many TELNET connections and improperly ending these connections, aka Bug ID CSCug35507.

The NAT process on Cisco Adaptive Security Appliances (ASA) devices allows remote attackers to cause a denial of service (connections-table memory consumption) via crafted packets, aka Bug ID CSCue46386.

The traffic engineering (TE) processing subsystem in Cisco IOS XR allows remote attackers to cause a denial of service (process restart) via crafted TE packets, aka Bug ID CSCue04000.

Cisco Unified Communications Domain Manager allows remote attackers to cause a denial of service (CPU consumption) via a flood of malformed UDP packets, aka Bug ID CSCug47057.

Memory leak in Cisco Unity Connection 9.x allows remote attackers to cause a denial of service (memory consumption and process crash) by sending many TCP requests, aka Bug ID CSCud59736.

Cisco Unified Communications Manager (CUCM) does not properly limit the rate of authentication attempts, which allows remote attackers to cause a denial of service (application slowdown) via a series of requests, aka Bug ID CSCud39515.

A vulnerability in the host input API daemon of Cisco Firepower Management Center (FMC) 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 certificate validation. An attacker could exploit this vulnerability by sending a crafted data stream to the host input daemon of the affected device. A successful exploit could allow the attacker to cause the host input daemon to restart. The attacker could use repeated attacks to cause the daemon to continuously reload, creating a DoS condition for the API.

OpenSSL 0.9.6k allows remote attackers to cause a denial of service (crash via large recursion) via malformed ASN.1 sequences.

A vulnerability in the UDP processing code of Cisco IOS 15.1, 15.2, and 15.4 and IOS XE 3.14 through 3.18 could allow an unauthenticated, remote attacker to cause the input queue of an affected system to hold UDP packets, causing an interface queue wedge and a denial of service (DoS) condition. The vulnerability is due to Cisco IOS Software application changes that create UDP sockets and leave the sockets idle without closing them. An attacker could exploit this vulnerability by sending UDP packets with a destination port of 0 to an affected device. A successful exploit could allow the attacker to cause UDP packets to be held in the input interfaces queue, resulting in a DoS condition. The input interface queue will stop holding UDP packets when it receives 250 packets. Cisco Bug IDs: CSCup10024, CSCva55744, CSCva95506.

Cisco Sourcefire Snort 3.0 before build 233 mishandles Ether Type Validation. Since valid ether type and IP protocol numbers do not overlap, Snort++ stores all protocol decoders in a single array. That makes it possible to craft packets that have IP protocol numbers in the ether type field which will confuse the Snort++ decoder. For example, an eth:llc:snap:icmp6 packet will cause a crash because there is no ip6 header with which to calculate the icmp6 checksum. Affected decoders include gre, llc, trans_bridge, ciscometadata, linux_sll, and token_ring. The fix adds a check in the packet manager to validate the ether type before indexing the decoder array. An out of range ether type will raise 116:473.

Cisco Sourcefire Snort 3.0 before build 233 has a Buffer Overread related to use of a decoder array. The size was off by one making it possible to read past the end of the array with an ether type of 0xFFFF. Increasing the array size solves this problem.

A vulnerability in the web-based management interface of Cisco AsyncOS for Cisco Email Security Appliance (ESA), Cisco Web Security Appliance (WSA), and Cisco Content Security Management Appliance (SMA) could allow an unauthenticated remote attacker to cause high CPU usage on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of specific HTTP request headers. An attacker could exploit this vulnerability by sending a malformed HTTP request to an affected device. A successful exploit could allow the attacker to trigger a prolonged status of high CPU utilization relative to the GUI process(es). Upon successful exploitation of this vulnerability, an affected device will still be operative, but its response time and overall performance may be degraded.

A vulnerability in the ingress processing of fragmented TCP packets by Cisco Wide Area Application Services (WAAS) could allow an unauthenticated, remote attacker to cause the WAASNET process to restart unexpectedly, causing a denial of service (DoS) condition. More Information: CSCvc57428. Known Affected Releases: 6.3(1). Known Fixed Releases: 6.3(0.143) 6.2(3c)6 6.2(3.22).

Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic 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 memory resource management while the Snort detection engine is processing ICMP packets. An attacker could exploit this vulnerability by sending a series of ICMP packets through an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device, causing the device to reload.

A vulnerability in the Border Gateway Protocol (BGP) processing functionality of the Cisco StarOS operating system for Cisco ASR 5000 Series Routers and Cisco Virtualized Packet Core (VPC) Software could allow an unauthenticated, remote attacker to cause the BGP process on an affected system to reload, resulting in a denial of service (DoS) condition. This vulnerability affects the following products if they are running the Cisco StarOS operating system and BGP is enabled for the system: Cisco ASR 5000 Series Routers and Cisco Virtualized Packet Core Software. More Information: CSCvc44968. Known Affected Releases: 16.4.1 19.1.0 21.1.0 21.1.M0.65824. Known Fixed Releases: 21.3.A0.65902 21.2.A0.65905 21.1.b0.66164 21.1.V0.66014 21.1.R0.65898 21.1.M0.65894 21.1.0.66030 21.1.0.

A vulnerability in the web-based management interface of Cisco Small Business 200 Series Smart Switches, Cisco Small Business 300 Series Managed Switches, and Cisco Small Business 500 Series Stackable Managed Switches could allow an unauthenticated, remote attacker to render the web-based management interface unusable, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to cause a permanent invalid redirect for requests sent to the web-based management interface of the device, resulting in a DoS condition.

A vulnerability in SSL/TLS message handler for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because incoming SSL/TLS packets are not properly processed. An attacker could exploit this vulnerability by sending a crafted SSL/TLS packet to 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 TCP throttling process of Cisco UCS C-Series Rack Servers 3.0(0.234) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient rate-limiting protection. An attacker could exploit this vulnerability by sending a high rate of TCP SYN packets to a specific TCP listening port on an affected device. An exploit could allow the attacker to cause a specific TCP listening port to stop accepting new connections, resulting in a DoS condition. Cisco Bug IDs: CSCva65544.

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.

tacacsd in Cisco IOS XR 5.1 and earlier allows remote attackers to cause a denial of service (process reload) via a malformed TACACS+ packet, aka Bug ID CSCum00468.

Multiple vulnerabilities in the implementation of the Common Industrial Protocol (CIP) feature in Cisco IOS 12.4 through 15.6 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 crafted CIP packets destined to an affected device. An attacker could exploit these vulnerabilities by sending crafted CIP packets 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. Cisco Bug IDs: CSCvc43709.

The XML API service in the Fabric Interconnect component in Cisco Unified Computing System (UCS) allows remote attackers to cause a denial of service (API service outage) via a malformed XML document in a packet, aka Bug ID CSCtg48206.

Multiple vulnerabilities in the implementation of the Common Industrial Protocol (CIP) feature in Cisco IOS 12.4 through 15.6 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 crafted CIP packets destined to an affected device. An attacker could exploit these vulnerabilities by sending crafted CIP packets 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. Cisco Bug IDs: CSCuz95334.

The DMVPN tunnel implementation in Cisco IOS 15.2 allows remote attackers to cause a denial of service (persistent IKE state) via a large volume of hub-to-spoke traffic, aka Bug ID CSCtq39602.

A vulnerability in the gRPC code of Cisco IOS XR Software for Cisco Network Convergence System (NCS) 5500 Series Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition when the emsd service stops. The vulnerability is due to the software's inability to process HTTP/2 packets. An attacker could exploit this vulnerability by sending a malformed HTTP/2 frame to the affected device. A successful exploit could allow the attacker to create a DoS condition when the emsd service stops. Cisco Bug IDs: CSCvb99388.

sensorApp on Cisco IPS 4200 series sensors 6.0, 6.2, and 7.0 does not properly allocate memory, which allows remote attackers to cause a denial of service (memory corruption and process crash, and traffic-inspection outage) via network traffic, aka Bug ID CSCtn23051.

A vulnerability in SSL traffic decryption for Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause depletion of system memory, aka a Firepower Detection Engine SSL Decryption Memory Consumption Denial of Service vulnerability. If this memory leak persists over time, a denial of service (DoS) condition could develop because traffic can cease to be forwarded through the device. The vulnerability is due to an error in how the Firepower Detection Snort Engine handles SSL traffic decryption and notifications to and from the Adaptive Security Appliance (ASA) handler. An attacker could exploit this vulnerability by sending a steady stream of malicious Secure Sockets Layer (SSL) traffic through the device. An exploit could allow the attacker to cause a DoS condition when the device runs low on system memory. This vulnerability affects Cisco Firepower Threat Defense (FTD) Software Releases 6.0.1 and later, running on any of the following Cisco products: Adaptive Security Appliance (ASA) 5500-X Series Next-Generation Firewalls, Firepower 2100 Series Security Appliances, Firepower 4100 Series Security Appliances, Firepower 9300 Series Security Appliances. Cisco Bug IDs: CSCve02069.

A vulnerability in the Independent Computing Architecture (ICA) accelerator feature for the Cisco Wide Area Application Services (WAAS) could allow an unauthenticated, remote attacker to cause an ICA application optimization-related process to restart, resulting in a partial denial of service (DoS) condition. The vulnerability is due to improperly aborting a connection when an unexpected protocol packet is received. An attacker could exploit this vulnerability by sending a crafted ICA traffic through the targeted device. A successful exploit could allow the attacker to cause a DoS condition that is due to a process unexpectedly restarting. The Cisco WAAS could drop ICA traffic while the process is restarting. This vulnerability affects Cisco Wide Area Application Services (WAAS) and Cisco Virtual Wide Area Application Services (vWAAS). Cisco Bug IDs: CSCve74457.

A vulnerability in the HTTP web interface for Cisco Wide Area Application Services (WAAS) could allow an unauthenticated, remote attacker to cause an HTTP Application Optimization (AO) related process to restart, causing a partial denial of service (DoS) condition. The vulnerability is due to lack of input validation of user-supplied input parameters within an HTTP request. An attacker could exploit this vulnerability by sending a crafted HTTP request through the targeted device. An exploit could allow the attacker to cause a DoS condition due to a process unexpectedly restarting. The WAAS could drop traffic during the brief time the process is restarting. Cisco Bug IDs: CSCvc63048.

A vulnerability in the H.264 decoder function of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a Cisco Meeting Server media process to restart unexpectedly when it receives an illegal H.264 frame. The vulnerability is triggered by an H.264 frame that has an invalid picture parameter set (PPS) value. An attacker could exploit this vulnerability by sending a malformed H.264 frame to the targeted device. An exploit could allow the attacker to cause a denial of service (DoS) condition because the media process could restart. The media session should be re-established within a few seconds, during which there could be a brief interruption in service. Cisco Bug IDs: CSCvg12559.