Day: May 20, 2021

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.

Fixed Releases
At the time of publication, the release information in the following table(s) was accurate. See the Details section in the bug ID(s) at the top of this advisory for the most complete and current information.
The left column lists Cisco software releases, and the right column indicates whether a release was affected by the vulnerabilities described in this advisory and which release included the fix for these vulnerabilities.
Cisco FTD Software

Cisco FTD Software Release
First Fixed Release for these Vulnerabilities

Earlier than 6.2.21
Migrate to a fixed release.

6.2.2
Migrate to a fixed release.

6.2.3
Migrate to a fixed release.

6.3.0
Migrate to a fixed release.

6.4.0
6.4.0.12

6.5.0
Migrate to a fixed release.

6.6.0
6.6.42

6.7.0
6.7.0.2

1. Cisco FMC and FTD Software releases 6.0.1 and earlier, as well as releases 6.2.0 and 6.2.1, have reached end of software maintenance. Customers are advised to migrate to a supported release that includes the fix for this vulnerability.

2. The First Fixed Release for the 6.6.0 code train was 6.6.3; however, due to upgrade issues associated with CSCvx86231 the recommended release is 6.6.4.

To upgrade to a fixed release of Cisco FTD Software, do one of the following:

For devices that are managed by using Cisco Firepower Management Center (FMC), use the FMC interface to install the upgrade. After installation is complete, reapply the access control policy.
For devices that are managed by using Cisco Firepower Device Manager (FDM), use the FDM interface to install the upgrade. After installation is complete, reapply the access control policy.

Cisco IOS XE Software and Cisco IOS XE SD-WAN Software

Cisco UTD Snort IPS Engine Software for IOS XE and Cisco UTD Engine for IOS XE SD-WAN Software1
First Fixed Release for these Vulnerabilities

Earlier than 16.12
Migrate to a fixed release.

16.12
16.12.5

17.1
Migrate to a fixed release.

17.2
Migrate to a fixed release.

17.3
17.3.3

17.4
17.4.1

1Starting with release 17.2.1, Cisco IOS XE Software and Cisco IOS XE SD-WAN Software share the same image file.
Open Source Snort
The open source Snort project releases 2.9.17.1 and later contain the fix for these vulnerabilities. For more information on open source Snort, see the Snort website.

While this workaround has been deployed and was proven successful in a test environment, customers should determine the applicability and effectiveness in their own environment and under their own use conditions. Customers should be aware that any workaround or mitigation that is implemented may negatively impact the functionality or performance of their network based on intrinsic customer deployment scenarios and limitations. Customers should not deploy any workarounds or mitigations before first evaluating the applicability to their own environment and any impact to such environment.
Cisco FTD Software Release 6.7.0
For Cisco FTD Software Release 6.7.0, as a workaround when the Snort 3 configuration option is enabled, an administrator may enable built-in rule 129:2 in the intrusion policy and set the action to Drop instead of Alert.
Use the following steps to verify that the Snort 3 configuration option is enabled. For more details, see the Switching Between Snort 2 and Snort 3 section of the Cisco Firepower Threat Defense Configuration Guide for Firepower Device Manager, Version 6.7.

Log in to the Admin Portal for the FTD deployment.
Navigate to Policies  > Intrusion.
Look for the Snort Version line above the table. The current version is the first number in the complete version number. For example, 2.9.17-95 is a Snort 2 version.

Use the following steps to enable rule 129:2. For more details, see the Changing Intrusion Rule Actions (Snort 3) section of the Cisco Firepower Threat Defense Configuration Guide for Firepower Device Manager, Version 6.7.

Log in to the Admin Portal for the FTD deployment.
Navigate to Policies  > Intrusion.
Choose any system-provided policy, such as Balanced Security and Connectivity.
Search for rule 129:2.
Check the check box next to the rule to enable it.
Choose Drop from the Action drop-down list.
Add the intrusion policy to a rule in Access control policy.