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: 7.7EPSS: 0%CPEs: 834EXPL: 0CVE-2021-34699 – Cisco IOS and IOS XE Software TrustSec CLI Parser Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-34699
A vulnerability in the TrustSec CLI parser of Cisco IOS and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. This vulnerability is due to an improper interaction between the web UI and the CLI parser. An attacker could exploit this vulnerability by requesting a particular CLI command to be run through the web UI. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Una vulnerabilidad en el analizador TrustSec CLI de Cisco IOS and Cisco IOS XE Software podría permitir a un atacante remoto y autenticado causar una recarga de un dispositivo afectado. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-trustsec-dos-7fuXDR2 • CWE-435: Improper Interaction Between Multiple Correctly-Behaving Entities CWE-436: Interpretation Conflict •
CVSS: 5.8EPSS: 0%CPEs: 302EXPL: 0CVE-2021-1377 – Cisco IOS and IOS XE Software ARP Resource Management Exhaustion Denial of Service Vulnerability
https://notcve.org/view.php?id=CVE-2021-1377
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. Una vulnerabilidad en la administración del Address Resolution Protocol (ARP) del Software Cisco IOS y el Software Cisco IOS XE, podría permitir a un atacante remoto no autenticado impedir que un dispositivo afectado resuelva entradas ARP para hosts legítimos en las subredes conectadas. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-arp-mtfhBfjE • CWE-399: Resource Management Errors •
CVSS: 6.9EPSS: 0%CPEs: 257EXPL: 0CVE-2021-1398 – Cisco IOS XE Software Arbitrary Code Execution Vulnerability
https://notcve.org/view.php?id=CVE-2021-1398
A vulnerability in the boot logic of Cisco IOS XE Software could allow an authenticated, local attacker with level 15 privileges or an unauthenticated attacker with physical access to execute arbitrary code on the underlying Linux operating system of an affected device. This vulnerability is due to incorrect validations of specific function arguments that are passed to the boot script. An attacker could exploit this vulnerability by tampering with a specific file, which an affected device would process during the initial boot process. On systems that are protected by the Unified Extensible Firmware Interface (UEFI) secure boot feature, a successful exploit could allow the attacker to execute unsigned code at boot time and bypass the image verification check in the secure boot process of the affected device. Una vulnerabilidad en la lógica de arranque del Software Cisco IOS XE, podría permitir a un atacante local autenticado con privilegios de nivel 15 o un atacante no autenticado con acceso físico ejecutar código arbitrario en el sistema operativo Linux subyacente de un dispositivo afectado. • https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-XE-ACE-75K3bRWe • CWE-489: Active Debug Code •