Summary

• A vulnerability in the secure boot implementation of Cisco Secure Firewalls 3100 Series that are running Cisco Adaptive Security Appliance (ASA) Software or Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated attacker with physical access to the device to bypass the secure boot functionality.

  This vulnerability is due to a logic error in the boot process. An attacker could exploit this vulnerability by injecting malicious code into a specific memory location during the boot process of an affected device. A successful exploit could allow the attacker to execute persistent code at boot time and break the chain of trust.

  Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

  This advisory is available at the following link:
  https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fw3100-secure-boot-5M8mUh26

  This advisory is part of the November 2022 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication. For a complete list of the advisories and links to them, see Cisco Event Response: November 2022 Semiannual Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication.

Affected Products

• Vulnerable Products

  This vulnerability affects Cisco Secure Firewalls 3100 Series if they were running a release of Cisco ASA Software or Cisco FTD Software that includes a vulnerable firmware bundle version:

  • In Cisco ASA Software Release 9.17 and Cisco FTD Software Release 7.1, firmware bundle versions earlier than 1.0.22 are vulnerable.
  • In Cisco ASA Software Release 9.18 and Cisco FTD Software Release 7.2, firmware bundle versions earlier than 1.2.17 are vulnerable.

  For information about which Cisco software releases are vulnerable, see the Fixed Software section of this advisory.

  Determine the Firmware Bundle Version

  To determine which firmware bundle is running on a device, use the show version detail CLI command at the Cisco FXOS CLI and look for the line starting with Firmware-Vers. For information on how to log in to the Cisco FXOS CLI, see the Cisco FXOS Troubleshooting Guide for the Firepower 1000/2100 and Secure Firewall 3100 with Firepower Threat Defense.

  The following example shows the output of the show version detail command on a device that is running firmware bundle release 1.2.15:

  firepower# show version detail
    Version: 7.2.0-82
    Startup-Vers: 7.2.0-82
  MANAGER:
      Boot Loader:
          Firmware-Vers: 1.2.15
          Rommon-Vers: 1.1.08
          Fpga-Vers: 0.19.00
          Fpga-Golden-Vers: 0.17.00
          NpuFpga-Vers: 1024.37.00
          TamFpga-Vers: 2.6.c
          Power-Sequencer-Vers: 1.6
          Firmware-Status: OK

   

  Products Confirmed Not Vulnerable

  Only products listed in the Vulnerable Products section of this advisory are known to be affected by this vulnerability.

  Cisco has confirmed that this vulnerability does not affect Cisco Firepower Management Center (FMC) Software.

Workarounds

• There are no workarounds that address this vulnerability.

Fixed Software

• 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.

  Fixed Releases

  In the following table(s), the left column lists Cisco software releases. The center column lists the firmware bundle version that includes the fix for the vulnerability that is described in this advisory. The right column lists the first software release that includes the fixed firmware bundle. Customers are advised to upgrade to an appropriate fixed software release as indicated in this section.

  Cisco ASA Software Release	First Fixed Firmware Bundle Version	First Fixed Release That Includes the Fixed Firmware Bundle
  9.17	1.0.22	9.17.1.15
  9.18	1.2.17	9.18.2

   

  Cisco FTD Software Release	First Fixed Firmware Bundle Version	First Fixed Release That Includes the Fixed Firmware Bundle
  7.1	1.0.22	7.1.0.2
  7.2	1.2.17	7.2.1

  Note: When Cisco ASA Software or FTD Software is upgraded on a device, the firmware bundle version is also upgraded automatically. If the Cisco ASA Software or FTD Software is later downgraded, the firmware bundle version is not downgraded. Once the firmware bundle is upgraded to a fixed version, it will remain fixed, even if the Cisco ASA Software or FTD Software is downgraded.

  For instructions on upgrading your FTD device, see Cisco Firepower Management Center Upgrade Guide.

   

  Additional Resources

  For help determining the best Cisco ASA, FTD, or FMC Software release, see the following Recommended Releases documents. If a security advisory recommends a later release, Cisco recommends following the advisory guidance.

  Cisco ASA Compatibility
  Cisco Secure Firewall ASA Upgrade Guide
  Cisco Secure Firewall Threat Defense Compatibility Guide

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

Exploitation and Public Announcements

• The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

Source

• This vulnerability was found during internal security testing.

URL

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fw3100-secure-boot-5M8mUh26

Revision History

• Version	Description	Section	Status	Date
  1.0	Initial public release.	—	Final	2022-NOV-09

  Show Less

---