// For flags

CVE-2021-1625

Cisco IOS XE Software Zone-Based Policy Firewall ICMP and UDP Inspection Vulnerability

Severity Score

5.8
*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 Zone-Based Policy Firewall feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to prevent the Zone-Based Policy Firewall from correctly classifying traffic. This vulnerability exists because ICMP and UDP responder-to-initiator flows are not inspected when the Zone-Based Policy Firewall has either Unified Threat Defense (UTD) or Application Quality of Experience (AppQoE) configured. An attacker could exploit this vulnerability by attempting to send UDP or ICMP flows through the network. A successful exploit could allow the attacker to inject traffic through the Zone-Based Policy Firewall, resulting in traffic being dropped because it is incorrectly classified or in incorrect reporting figures being produced by high-speed logging (HSL).

Una vulnerabilidad en la funcionalidad Zone-Based Policy Firewall de Cisco IOS XE Software podría permitir a un atacante remoto no autenticado impedir que el Zone-Based Policy Firewall clasifique correctamente el tráfico. Esta vulnerabilidad se presenta porque los flujos ICMP y UDP de respuesta a iniciador no se inspeccionan cuando el Firewall de Políticas Basado en la Zona tiene configurada la Defensa Unificada contra Amenazas (UTD) o la Calidad de Experiencia de las Aplicaciones (AppQoE). Un atacante podría explotar esta vulnerabilidad al intentar enviar de flujos UDP o ICMP mediante la red. Una explotación con éxito podría permitir al atacante inyectar tráfico mediante Firewall de Políticas Basado en Zonas, resultando en la eliminación de tráfico por estar clasificado incorrectamente o a la producción de cifras de informes incorrectas por parte del registro de alta velocidad (HSL)

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
Low
Availability
None
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:Attend
Exploitation
None
Automatable
Yes
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2020-11-13 CVE Reserved
  • 2021-09-23 CVE Published
  • 2024-09-26 EPSS Updated
  • 2024-11-07 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-284: Improper Access Control
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"
< 17.3.2
Search vendor "Cisco" for product "Ios Xe" and version " < 17.3.2"
-
Affected