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

Published Mar 24, 2021
·
Updated

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.

Affected Software

265 affected components
Cisco IOS XE=3.7.0bs
Cisco IOS XE=3.7.0s
Cisco IOS XE=3.7.0xas
Cisco IOS XE=3.7.0xbs
Cisco IOS XE=3.7.1as
Cisco IOS XE=3.7.1s
Cisco IOS XE=3.7.2s
Cisco IOS XE=3.7.2ts
Cisco IOS XE=3.7.3s
Cisco IOS XE=3.7.4as
Cisco IOS XE=3.7.4s
Cisco IOS XE=3.7.5s
Cisco IOS XE=3.7.6s
Cisco IOS XE=3.7.7s
Cisco IOS XE=3.7.8s
Cisco IOS XE=3.8.0s
Cisco IOS XE=3.8.1s
Cisco IOS XE=3.8.2s
Cisco IOS XE=3.9.0as
Cisco IOS XE=3.9.0s
Cisco IOS XE=3.9.0xas
Cisco IOS XE=3.9.1as
Cisco IOS XE=3.9.1s
Cisco IOS XE=3.9.2s
Cisco IOS XE=3.10.0s
Cisco IOS XE=3.10.1s
Cisco IOS XE=3.10.1xbs
Cisco IOS XE=3.10.1xcs
Cisco IOS XE=3.10.2as
Cisco IOS XE=3.10.2s
Cisco IOS XE=3.10.2ts
Cisco IOS XE=3.10.3s
Cisco IOS XE=3.10.4s
Cisco IOS XE=3.10.5s
Cisco IOS XE=3.10.6s
Cisco IOS XE=3.10.7s
Cisco IOS XE=3.10.8as
Cisco IOS XE=3.10.8s
Cisco IOS XE=3.10.9s
Cisco IOS XE=3.10.10s
Cisco IOS XE=3.11.0s
Cisco IOS XE=3.11.1s
Cisco IOS XE=3.11.2s
Cisco IOS XE=3.11.3s
Cisco IOS XE=3.11.4s
Cisco IOS XE=3.12.0as
Cisco IOS XE=3.12.0s
Cisco IOS XE=3.12.1s
Cisco IOS XE=3.12.2s
Cisco IOS XE=3.12.3s
Cisco IOS XE=3.12.4s
Cisco IOS XE=3.13.0as
Cisco IOS XE=3.13.0s
Cisco IOS XE=3.13.1s
Cisco IOS XE=3.13.2as
Cisco IOS XE=3.13.2s
Cisco IOS XE=3.13.3s
Cisco IOS XE=3.13.4s
Cisco IOS XE=3.13.5as
Cisco IOS XE=3.13.5s
Cisco IOS XE=3.13.6as
Cisco IOS XE=3.13.6bs
Cisco IOS XE=3.13.6s
Cisco IOS XE=3.13.7as
Cisco IOS XE=3.13.7s
Cisco IOS XE=3.13.8s
Cisco IOS XE=3.13.9s
Cisco IOS XE=3.13.10s
Cisco IOS XE=3.14.0s
Cisco IOS XE=3.14.1s
Cisco IOS XE=3.14.2s
Cisco IOS XE=3.14.3s
Cisco IOS XE=3.14.4s
Cisco IOS XE=3.15.0s
Cisco IOS XE=3.15.1cs
Cisco IOS XE=3.15.1s
Cisco IOS XE=3.15.1xbs
Cisco IOS XE=3.15.2s
Cisco IOS XE=3.15.2xbs
Cisco IOS XE=3.15.3s
Cisco IOS XE=3.15.4s
Cisco IOS XE=3.16.0as
Cisco IOS XE=3.16.0bs
Cisco IOS XE=3.16.0cs
Cisco IOS XE=3.16.0s
Cisco IOS XE=3.16.1as
Cisco IOS XE=3.16.1s
Cisco IOS XE=3.16.2as
Cisco IOS XE=3.16.2bs
Cisco IOS XE=3.16.2s
Cisco IOS XE=3.16.3as
Cisco IOS XE=3.16.3s
Cisco IOS XE=3.16.4as
Cisco IOS XE=3.16.4bs
Cisco IOS XE=3.16.4cs
Cisco IOS XE=3.16.4ds
Cisco IOS XE=3.16.4es
Cisco IOS XE=3.16.4gs
Cisco IOS XE=3.16.4s
Cisco IOS XE=3.16.5as
Cisco IOS XE=3.16.5bs
Cisco IOS XE=3.16.5s
Cisco IOS XE=3.16.6bs
Cisco IOS XE=3.16.6s
Cisco IOS XE=3.16.7as
Cisco IOS XE=3.16.7bs
Cisco IOS XE=3.16.7s
Cisco IOS XE=3.16.8s
Cisco IOS XE=3.16.9s
Cisco IOS XE=3.16.10as
Cisco IOS XE=3.16.10s
Cisco IOS XE=3.17.0s
Cisco IOS XE=3.17.1as
Cisco IOS XE=3.17.1s
Cisco IOS XE=3.17.2s
Cisco IOS XE=3.17.3s
Cisco IOS XE=3.17.4s
Cisco IOS XE=3.18.0as
Cisco IOS XE=3.18.0s
Cisco IOS XE=3.18.0sp
Cisco IOS XE=3.18.1asp
Cisco IOS XE=3.18.1bsp
Cisco IOS XE=3.18.1csp
Cisco IOS XE=3.18.1gsp
Cisco IOS XE=3.18.1hsp
Cisco IOS XE=3.18.1isp
Cisco IOS XE=3.18.1s
Cisco IOS XE=3.18.1sp
Cisco IOS XE=3.18.2asp
Cisco IOS XE=3.18.2s
Cisco IOS XE=3.18.2sp
Cisco IOS XE=3.18.3asp
Cisco IOS XE=3.18.3bsp
Cisco IOS XE=3.18.3s
Cisco IOS XE=3.18.3sp
Cisco IOS XE=3.18.4s
Cisco IOS XE=3.18.4sp
Cisco IOS XE=3.18.5sp
Cisco IOS XE=3.18.6sp
Cisco IOS XE=3.18.7sp
Cisco IOS XE=3.18.8asp
Cisco IOS XE=3.18.8sp
Cisco IOS XE=16.1.1
Cisco IOS XE=16.1.2
Cisco IOS XE=16.1.3
Cisco IOS XE=16.2.1
Cisco IOS XE=16.2.2
Cisco IOS XE=16.3.1
Cisco IOS XE=16.3.1a
Cisco IOS XE=16.3.2
Cisco IOS XE=16.3.3
Cisco IOS XE=16.3.4
Cisco IOS XE=16.3.5
Cisco IOS XE=16.3.5b
Cisco IOS XE=16.3.6
Cisco IOS XE=16.3.7
Cisco IOS XE=16.3.8
Cisco IOS XE=16.3.9
Cisco IOS XE=16.3.10
Cisco IOS XE=16.3.11
Cisco IOS XE=16.4.1
Cisco IOS XE=16.4.2
Cisco IOS XE=16.4.3
Cisco IOS XE=16.5.1
Cisco IOS XE=16.5.1a
Cisco IOS XE=16.5.1b
Cisco IOS XE=16.5.2
Cisco IOS XE=16.5.3
Cisco IOS XE=16.6.1
Cisco IOS XE=16.6.2
Cisco IOS XE=16.6.3
Cisco IOS XE=16.6.4
Cisco IOS XE=16.6.4a
Cisco IOS XE=16.6.4s
Cisco IOS XE=16.6.5
Cisco IOS XE=16.6.5a
Cisco IOS XE=16.6.5b
Cisco IOS XE=16.6.6
Cisco IOS XE=16.6.7
Cisco IOS XE=16.6.7a
Cisco IOS XE=16.6.8
Cisco IOS XE=16.7.1
Cisco IOS XE=16.7.1a
Cisco IOS XE=16.7.1b
Cisco IOS XE=16.7.2
Cisco IOS XE=16.7.3
Cisco IOS XE=16.7.4
Cisco IOS XE=16.8.1
Cisco IOS XE=16.8.1a
Cisco IOS XE=16.8.1b
Cisco IOS XE=16.8.1c
Cisco IOS XE=16.8.1d
Cisco IOS XE=16.8.1e
Cisco IOS XE=16.8.1s
Cisco IOS XE=16.8.2
Cisco IOS XE=16.8.3
Cisco IOS XE=16.9.1
Cisco IOS XE=16.9.1a
Cisco IOS XE=16.9.1b
Cisco IOS XE=16.9.1c
Cisco IOS XE=16.9.1d
Cisco IOS XE=16.9.1s
Cisco IOS XE=16.9.2
Cisco IOS XE=16.9.2a
Cisco IOS XE=16.9.2s
Cisco IOS XE=16.9.3
Cisco IOS XE=16.9.3a
Cisco IOS XE=16.9.3h
Cisco IOS XE=16.9.3s
Cisco IOS XE=16.9.4
Cisco IOS XE=16.9.4c
Cisco IOS XE=16.9.5
Cisco IOS XE=16.9.5f
Cisco IOS XE=16.9.6
Cisco IOS XE=16.10.1
Cisco IOS XE=16.10.1a
Cisco IOS XE=16.10.1b
Cisco IOS XE=16.10.1c
Cisco IOS XE=16.10.1d
Cisco IOS XE=16.10.1e
Cisco IOS XE=16.10.1f
Cisco IOS XE=16.10.1g
Cisco IOS XE=16.10.1s
Cisco IOS XE=16.10.2
Cisco IOS XE=16.10.3
Cisco IOS XE=16.11.1
Cisco IOS XE=16.11.1a
Cisco IOS XE=16.11.1b
Cisco IOS XE=16.11.1c
Cisco IOS XE=16.11.1s
Cisco IOS XE=16.11.2
Cisco IOS XE=16.12.1
Cisco IOS XE=16.12.1a
Cisco IOS XE=16.12.1c
Cisco IOS XE=16.12.1s
Cisco IOS XE=16.12.1t
Cisco IOS XE=16.12.1w
Cisco IOS XE=16.12.1x
Cisco IOS XE=16.12.1y
Cisco IOS XE=16.12.1z
Cisco IOS XE=16.12.1z1
Cisco IOS XE=16.12.1za
Cisco IOS XE=16.12.2
Cisco IOS XE=16.12.2a
Cisco IOS XE=16.12.2s
Cisco IOS XE=16.12.2t
Cisco IOS XE=16.12.3
Cisco IOS XE=16.12.3a
Cisco IOS XE=16.12.3s
Cisco IOS XE=16.12.4
Cisco IOS XE=16.12.4a
Cisco IOS XE=17.1.1
Cisco IOS XE=17.1.1a
Cisco IOS XE=17.1.1s
Cisco IOS XE=17.1.1t
Cisco IOS XE=17.1.2
Cisco IOS XE=17.2.1
Cisco IOS XE=17.2.1a
Cisco IOS XE=17.2.1r
Cisco IOS XE=17.2.1v
Cisco IOS XE=17.2.2
Cisco IOS XE=17.2.3
Cisco IOS XE=17.3.1
Cisco IOS XE=17.3.1a
Cisco IOS XE=17.3.1w

Event History

Mar 24, 2021
CVE Published
via MITRE·08:06 PM
Data Sourced
via MITRE·08:06 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2021-1446?

CVE-2021-1446 has a critical severity rating, as it could allow an unauthenticated remote attacker to cause the affected device to reload.

2

How do I fix CVE-2021-1446?

To fix CVE-2021-1446, update your Cisco IOS XE software to a version that addresses the vulnerability.

3

What types of devices are affected by CVE-2021-1446?

CVE-2021-1446 affects Cisco IOS XE devices with specific versions that utilize the DNS ALG functionality in NAT.

4

Can CVE-2021-1446 be exploited remotely?

Yes, CVE-2021-1446 can be exploited remotely without authentication, making it particularly dangerous.

5

What are the potential impacts of CVE-2021-1446?

The potential impacts of CVE-2021-1446 include unexpected device reloads, leading to service disruption.

Company

Resources

Contact

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