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. A successful exploit could allow the attacker to cause the affected device to crash, resulting in a reload of the device.

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. A successful exploit could allow the attacker to cause the affected device to crash, resulting in a reload of the device.

Una vulnerabilidad en el analizador de mensajes Link Layer Discovery Protocol (LLDP) de Cisco IOS Software and Cisco IOS XE Software podría permitir a un atacante desencadenar una recarga de un dispositivo afectado, resultando en una condición de denegación de servicio (DoS). Esta vulnerabilidad es debido a una inicialización inapropiada de un búfer. Un atacante podría explotar esta vulnerabilidad por cualquiera de los siguientes métodos: Un atacante autenticado y remoto podría acceder a la tabla de vecinos LLDP por medio de la CLI o SNMP mientras el dispositivo está en un estado específico. Un atacante adyacente no autenticado podría corromper la tabla de vecinos LLDP inyectando tramas LLDP específicas en la red y luego esperar a que un administrador del dispositivo o un sistema de administración de red (NMS) que administre el dispositivo recupere la tabla de vecinos LLDP del dispositivo por medio de la CLI o SNMP. Un atacante autenticado y adyacente con credenciales SNMP de sólo lectura o con privilegios bajos en la CLI del dispositivo podría corromper la tabla de vecinos LLDP inyectando tramas LLDP específicas en la red y luego accediendo a la tabla de vecinos LLDP por medio de la CLI o SNMP. Una explotación con éxito podría permitir al atacante causar el bloqueo del dispositivo afectado, resultando en una recarga del dispositivo