CVE-2021-1446 HIGH

CVE-2021-1446: Cisco IOS XE Software DNS NAT Protocol Application Layer Gateway Denial of Service Vulnerability

Vendor Cisco
Product Cisco IOS XE Software
Weakness CWE-754
Published March 24, 2021
Last update November 8, 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

A vulnerability in the DNS application layer gateway (ALG) functionality used by Network Address Translation (NAT) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a logic error that occurs when an affected device inspects certain DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through an affected device that is performing NAT for DNS packets. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability can be exploited only by traffic that is sent through an affected device via IPv4 packets. The vulnerability cannot be exploited via IPv6 traffic.

Key dates

02Disclosure timeline

March 24, 2021 CVE published
November 8, 2024 Record updated