CVSS: 7.4EPSS: 0%CPEs: 251EXPL: 0CVE-2021-34714 – Multiple Cisco Operating Systems Unidirectional Link Detection Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-34714
A vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software, Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. This vulnerability is due to improper input validation of the UDLD packets. An attacker could exploit this vulnerability by sending specifically crafted UDLD packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ • CWE-20: Improper Input Validation •
CVSS: 6.8EPSS: 0%CPEs: 203EXPL: 0CVE-2021-34703 – Cisco IOS and IOS XE Software Link Layer Discovery Protocol Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-34703
A vulnerability in the Link Layer Discovery Protocol (LLDP) message parser of Cisco IOS Software and Cisco IOS XE Software could allow an attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to improper initialization of a buffer. An attacker could exploit this vulnerability via any of the following methods: An authenticated, remote attacker could access the LLDP neighbor table via either the CLI or SNMP while the device is in a specific state. An unauthenticated, adjacent attacker could corrupt the LLDP neighbor table by injecting specific LLDP frames into the network and then waiting for an administrator of the device or a network management system (NMS) managing the device to retrieve the LLDP neighbor table of the device via either the CLI or SNMP. An authenticated, adjacent attacker with SNMP read-only credentials or low privileges on the device CLI could corrupt the LLDP neighbor table by injecting specific LLDP frames into the network and then accessing the LLDP neighbor table via either the CLI or SNMP. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-lldp-dos-sBnuHSjT • CWE-456: Missing Initialization of a Variable CWE-665: Improper Initialization •
CVSS: 9.8EPSS: 0%CPEs: 135EXPL: 0CVE-2020-3284 – Cisco IOS XR Software Enhanced Preboot eXecution Environment Unsigned Code Execution Vulnerability
https://notcve.org/view.php?id=CVE-2020-3284
A vulnerability in the enhanced Preboot eXecution Environment (PXE) boot loader for Cisco IOS XR 64-bit Software could allow an unauthenticated, remote attacker to execute unsigned code during the PXE boot process on an affected device. The PXE boot loader is part of the BIOS and runs over the management interface of hardware platforms that are running Cisco IOS XR Software only. The vulnerability exists because internal commands that are issued when the PXE network boot process is loading a software image are not properly verified. An attacker could exploit this vulnerability by compromising the PXE boot server and replacing a valid software image with a malicious one. Alternatively, the attacker could impersonate the PXE boot server and send a PXE boot reply with a malicious file. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-pxe-unsign-code-exec-qAa78fD2 • CWE-284: Improper Access Control •
CVSS: 7.4EPSS: 0%CPEs: 149EXPL: 0CVE-2020-3508 – Cisco IOS XE Software for Cisco ASR 1000 Series 20-Gbps Embedded Services Processor IP ARP Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2020-3508
A vulnerability in the IP Address Resolution Protocol (ARP) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation Services Routers with a 20-Gbps Embedded Services Processor (ESP) installed could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service condition. The vulnerability is due to insufficient error handling when an affected device has reached platform limitations. An attacker could exploit this vulnerability by sending a malicious series of IP ARP messages to an affected device. A successful exploit could allow the attacker to exhaust system resources, which would eventually cause the affected device to reload. Una vulnerabilidad en la funcionalidad de Address Resolution Protocol (ARP) de IP de Cisco IOS XE Software para Cisco ASR 1000 Series Aggregation Services Routers con un Embedded Services Processor (ESP) de 20-Gbps instalado, podría permitir a un atacante adyacente no autenticado causar la recarga de un dispositivo afectado, resultando en una condición de denegación de servicio. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esp20-arp-dos-GvHVggqJ • CWE-400: Uncontrolled Resource Consumption •
CVSS: 7.4EPSS: 0%CPEs: 208EXPL: 0CVE-2020-3120 – Cisco FXOS, IOS XR, and NX-OS Software Cisco Discovery Protocol Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2020-3120
A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. • http://packetstormsecurity.com/files/156203/Cisco-Discovery-Protocol-CDP-Remote-Device-Takeover.html https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-fxnxos-iosxr-cdp-dos • CWE-190: Integer Overflow or Wraparound •