CVE-2020-3421 HIGH

CVE-2020-3421: Cisco IOS XE Software Zone-Based Firewall Denial of Service Vulnerabilities

Vendor Cisco
Product Cisco IOS XE Software
Weakness CWE-754
Published September 24, 2020
Last update November 13, 2024

CVSS base score

8.6/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

What the vulnerability does

01Description

Multiple vulnerabilities in the Zone-Based Firewall feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload or stop forwarding traffic through the firewall. The vulnerabilities are due to incomplete handling of Layer 4 packets through the device. An attacker could exploit these vulnerabilities by sending a certain sequence of traffic patterns through the device. A successful exploit could allow the attacker to cause the device to reload or stop forwarding traffic through the firewall, resulting in a denial of service. For more information about these vulnerabilities, see the Details section of this advisory.

Key dates

02Disclosure timeline

September 24, 2020 CVE published
November 13, 2024 Record updated