CVE-2022-20837

Cisco IOS XE Software DNS NAT Protocol Application Layer Gateway Denial of Service Vulnerability

Description

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

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.29%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XE Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-alg-dos-KU9Z8kFX vendor advisory

Frequently Asked Questions

What is the severity of CVE-2022-20837?
CVE-2022-20837 has been scored as a high severity vulnerability.
How to fix CVE-2022-20837?
To fix CVE-2022-20837, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-20837 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-20837 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-20837?
CVE-2022-20837 affects Cisco Cisco IOS XE Software.
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