// For flags

CVE-2020-3509

Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers DHCP Denial of Service Vulnerability

Severity Score

8.6
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Attend
*SSVC
Descriptions

A vulnerability in the DHCP message handler of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the supervisor to crash, which could result in a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when DHCP version 4 (DHCPv4) messages are parsed. An attacker could exploit this vulnerability by sending a malicious DHCPv4 message to or through a WAN interface of an affected device. A successful exploit could allow the attacker to cause a reload of the affected device. Note: On Cisco cBR-8 Converged Broadband Routers, all of the following are considered WAN interfaces: 10 Gbps Ethernet interfaces 100 Gbps Ethernet interfaces Port channel interfaces that include multiple 10 and/or 100 Gbps Ethernet interfaces

Una vulnerabilidad en el manejador de mensajes DHCP de Cisco IOS XE Software para Cisco cBR-8 Converged Broadband Routers, podría permitir a un atacante remoto no autenticado causar que el supervisor se bloquee, lo que podría resultar en una condición de denegación de servicio (DoS). La vulnerabilidad es debido a un manejo insuficiente de errores cuando son analizados los mensajes de DHCP versión 4 (DHCPv4). Un atacante podría explotar esta vulnerabilidad mediante el envío de un mensaje DHCPv4 malicioso o mediante una interfaz WAN de un dispositivo afectado. Una explotación con éxito podría permitir al atacante causar una recarga del dispositivo afectado. Nota: En Cisco cBR-8 Converged Broadband Routers, todos los siguientes son considerados interfaces WAN: Interfaces Ethernet de 10 Gbps, Interfaces Ethernet de 100 Gbps Interfaces de canal de puerto que incluyen múltiples interfaces Ethernet de 10 y/o 100 Gbps.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Attend
Exploitation
None
Automatable
Yes
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2019-12-12 CVE Reserved
  • 2020-09-24 CVE Published
  • 2023-06-10 EPSS Updated
  • 2024-11-13 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-203: Observable Discrepancy
  • CWE-388: 7PK - Errors
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Cisco
Search vendor "Cisco"
 Ios Xe
Search vendor "Cisco" for product "Ios Xe"
 16.7\(1\)
Search vendor "Cisco" for product "Ios Xe" and version "16.7\(1\)"
-
Affected
in Cisco
Search vendor "Cisco"
 Cbr-8
Search vendor "Cisco" for product "Cbr-8"
--
Safe