CVE-2023-20233: Null Pointer Dereference

Published Sep 13, 2023
·
Updated

A vulnerability in the Connectivity Fault Management (CFM) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to incorrect processing of invalid continuity check messages (CCMs). An attacker could exploit this vulnerability by sending crafted CCMs to an affected device. A successful exploit could allow the attacker to cause the CFM service to crash when a user displays information about maintenance end points (MEPs) for peer MEPs on an affected device.

Affected Software

5 affected components
Cisco IOS XR<7.5.4
Cisco IOS XR>=7.6<7.6.3
Cisco IOS XR>=7.7<7.7.21
Cisco IOS XR>=7.8<7.8.2
Cisco IOS XR=7.9.0

Event History

Sep 13, 2023
CVE Published
via MITRE·04:40 PM
Data Sourced
via MITRE·04:40 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2023-20233.

2

What is the severity of CVE-2023-20233?

The severity of CVE-2023-20233 is medium with a CVSS score of 6.5.

3

What is affected by CVE-2023-20233?

Cisco IOS XR Software versions up to 7.5.4, versions 7.6 up to 7.6.3, versions 7.7 up to 7.7.21, versions 7.8 up to 7.8.2, and version 7.9.0 are affected by CVE-2023-20233.

4

How can an attacker exploit CVE-2023-20233?

An unauthenticated, remote attacker can exploit CVE-2023-20233 by sending invalid continuity check messages to the device, causing a denial of service condition.

5

Are there any references for CVE-2023-20233?

Yes, you can find more information about CVE-2023-20233 in the [Cisco Security Advisory](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-xr-cfm-3pWN8MKt).

Contact

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