CVE-2023-20200: Cisco Security Advisory: Cisco Firepower 4100 Series, Firepower 9300 Security Appliances, and UCS 6300 Series Fabric Interconnects SNMP Denial of Service Vulnerability

• Cisco has released free software updates that address the vulnerability described in this advisory. Customers with service contracts that entitle them to regular software updates should obtain security fixes through their usual update channels.

  Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license:
  https://www.cisco.com/c/en/us/products/end-user-license-agreement.html

  Additionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.

  The Cisco Support and Downloads page on Cisco.com provides information about licensing and downloads. This page can also display customer device support coverage for customers who use the My Devices tool.

  When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories page, to determine exposure and a complete upgrade solution.

  In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.

  Customers Without Service Contracts

  Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco TAC: https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html

  Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.

  Cisco FXOS Software

  To help customers determine their exposure to vulnerabilities in Cisco FXOS Software, Cisco provides the Cisco Software Checker. This tool identifies any Cisco security advisories that impact a specific software release and the earliest release that fixes the vulnerabilities that are described in each advisory (“First Fixed”). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities that are described in all the advisories that the Software Checker identifies (“Combined First Fixed”).

  To use the tool, go to the Cisco Software Checker page and follow the instructions. Alternatively, use the following form to search for vulnerabilities that affect a specific software release. To use the form, follow these steps:

  1. Choose which advisories the tool will search-only this advisory, only advisories with a Critical or High Security Impact Rating (SIR), or all advisories.
  2. Choose the appropriate platform.
  3. Enter a release number-for example, 2.9.1.158 for Cisco Firepower 4100 Series Security Appliances.
  4. Click Check.

**Cisco UCS Software**

In the following table, the left column lists Cisco software releases. The center column indicates whether a release is affected by the vulnerability described in this advisory and the first release that includes the fix for this vulnerability. The right column indicates whether a release is affected by all of the High and Critical vulnerabilities described in this bundle and which release includes fixes for those vulnerabilities.

**UCS 6300 Series Fabric Interconnects**

Cisco UCS Software Release

First Fixed Release for This Vulnerability

First Fixed Release for All Vulnerabilities Described in the Bundle of Advisories

Earlier than 4.1

Migrate to a fixed release.

Migrate to a fixed release.

4.1

4.1(3l)

4.1(3l)

4.2

4.2(3b), 4.2(3d)1

4.2(3b), 4.2(3d)1

4.3

Not vulnerable.

Not vulnerable.

1\. 4.2(3d) is the first fixed release for Cisco UCS 6324 Fabric Interconnects. 4.2(3b) is the first fixed release for all other UCS 6300 Series Fabric Interconnect models.

The Cisco Product Security Incident Response Team (PSIRT) validates only the affected and fixed release information that is documented in this advisory.

**Additional Resources**

For help determining the best Cisco NX-OS Software release for a Cisco Nexus Switch, see the following Recommended Releases documents. If a security advisory recommends a later release, Cisco recommends following the advisory guidance.

> Cisco MDS Series Switches  
> Cisco Nexus 1000V for VMware Switch  
> Cisco Nexus 3000 Series Switches  
> Cisco Nexus 5500 Platform Switches  
> Cisco Nexus 5600 Platform Switches  
> Cisco Nexus 6000 Series Switches  
> Cisco Nexus 7000 Series Switches  
> Cisco Nexus 9000 Series Switches  
> Cisco Nexus 9000 Series ACI-Mode Switches

To determine the best release for Cisco UCS Software, see the Recommended Releases documents in the release notes for the device.