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Disable SSL 3.0 and TLS 1.0 on Forefront TMG and UAG 2010
When performing SSL and TLS hardening on Microsoft Forefront Threat Management Gateway (TMG) 2010 or Forefront Unified Access Gateway (UAG) 2010 servers, disabling SSL 3.0 and TLS 1.0 is often required to meet regulatory and compliance guidelines for security. However, disabling SSL 3.0 and TLS 1.0 causes the SQL Server (ISARS) and SQL Server Express services to fail on start up.
Switching from SQL logging to text file logging can be employed as a workaround. However, when using text file logging, generating historical reports in the TMG management console is no longer supported.
To restore full functionality for SQL logging and reporting when SSL 3.0 and TLS 1.0 are both disabled, an update to the local security policy of the server is required. Open the Local Security Policy editor by clicking on the Start button and navigating to Administrative Tools and Local Security Policy. Expand Local Policies and click on Security Options. Double-click on System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing. Click Enabled and then click OK.
Restart the computer for the changes to take effect. Once complete, all SQL services should start and run without issue.
Note: If Remote Desktop Services (RDS) is used to manage the Forefront TMG firewall it will be necessary to install update KB3080079.
Using PowerShell to Determine Forefront TMG Build Number
Identifying the current build number of your Forefront TMG 2010 installation is critically important when making changes or updates to the system. It is generally recommended that all TMG firewalls be on the same release, so having this information is essential. Many TMG administrators use the TMG management console to gather this information, but I can tell you based on experience that this is not always the most accurate method to use.
I much prefer to gather this information programmatically at the command line. In the past I’ve written about using VBScript to do this, but it’s almost 2016 now and we really should be using PowerShell whenever possible. To that end, here are a few lines of PowerShell code you can use to accurately determine which version and build number your TMG firewall is currently running.
$FPC = New-Object -ComObject FPC.Root $Server = $FPC.GetContainingServer() $Server.ProductVersion
If you’ve done any work at all with VBScript and the TMG’s FPC COM object, you’ll no doubt be able to convert some of your existing scripts to PowerShell. Also, PowerShell, with its tab auto completion, is much more discoverable than using VBScript with COM, so I’m sure you’ll be able to do a lot more with TMG using PowerShell.
Enjoy!
Reminder: Microsoft Reputation Services (MRS) End of Support
As a reminder to anyone out there still using the URL filtering feature of their Forefront TMG 2010 firewall, the Microsoft Reputation Services (MRS) service, which provides URL categorization for TMG, will no longer be supported after December 31, 2015. After this date, Microsoft will cease updating their URL categorization database. In addition, there are no guarantees from Microsoft that the service will be available in any form, so customers still using this service are strongly encouraged to look for alternative solutions.
For many organizations, this means migrating to another platform entirely, which is not a bad idea considering that TMG is nearly six years old now. Alternatively, it is possible to replace TMG’s web filtering component. This can be done on premises by using integrations from various third-party vendors, or by using a cloud-based solution such as Zscaler.
Regardless which path you take, you have just over one month to identify and implement another URL filtering solution. Good luck!
ISAinfo Forefront TMG 2010 Configuration Reporting Utility
With the demise of isatools.org a few years ago, many ISA Server and Forefront TMG 2010 administrators have reached out to me to ask where they can find the ISAinfo tool that was previously found on that site. If you’re not familiar with ISAinfo, it was a great utility used for viewing the ISA or TMG configuration by parsing the configuration export. This tool is tremendously useful for providing support, as it includes all of the information required to provide context for troubleshooting. In addition it is an excellent documentation tool.
So, if you’re looking for a reputable location from which to download this tool, look no further. I’ve placed the isainfo.zip file along with the checksums for file verification on my public OneDrive. Enjoy!
ISAinfo.zip – http://1drv.ms/1Q8GOaA
Checksums – http://1drv.ms/1Q8GWqq
Fastvue TMG Reporter 3.0 with Site Clean Now Available
Just a few months ago I wrote about the beta release of Fastvue’s TMG Reporter v3.0, which includes some compelling new features that TMG firewall administrators are sure to love. Today I’m happy to announce that TMG Reporter 3.0 is now generally available. If you’re still using Forefront TMG 2010 in production, you’ll certainly want to check out the latest features TMG Reporter v3.0 has to offer. Site Clean is sure to impress! Head over to the Fastvue blog for more information.
http://fastvue.co/tmgreporter/blog/fastvue-tmg-reporter-v3-0-out-now/
Fastvue TMG Reporter 3.0 Beta Now Available
I’m a huge fan of the Fastvue TMG Reporter advanced reporting solution. If you’ve spent any time at all with the native Forefront TMG 2010 reporting tools, you know they are, as my British friends say, “rubbish”. While it is possible to configure Forefront TMG 2010 to log to an external SQL server and create your own reports, a better alternative is to use Fastvue TMG Reporter. They’ve already done all the hard work for you! Also, TMG Reporter from Fastvue works with TMG when configured to use an external SQL server, so you get the best of both worlds!
Recently the fine folks at Fastvue announced a sneak peak at their latest update to TMG Reporter in v3.0 Beta. This latest release includes a bunch of great new features, including the following:
- Site Clean – This provides a way to clean up a lot of noise from your activity reports by consolidating related requests (e.g. analytics and CDN requests).
- Private Report Sharing – Create a report for an individual or group and prevent them from accessing any other report data.
- AD Security Group Filtering – A must have for searching activity reports!
- Export to CSV for Reports and Report Tables – Great feature for detailed, granular data analysis offline.
- Filter by Firewall Server Name or IP Address – This is essential for enterprise customers managing multiple TMG firewalls across the organization.
The latest release also includes Gantt Bars for Activity Reports, changes to the Productivity Dashboard, inclusion of search terms in User Overview reports, an updated Alerts interface, and improved data visibility. In addition, v3.0 includes memory usage improvements and the usual bug fixes and miscellaneous minor improvements.
Be sure to download Fastvue TMG Report v3.0 Beta today!
Forefront TMG 2010 SQL Services Fail to Start After Disabling SSL 3.0
When performing POODLE attack mitigation on the Forefront TMG 2010 firewall by disabling SSL 3.0, you may encounter a scenario in which TMG’s SQL services fail to start after a reboot.
Looking through the Windows system event log you may see an error message logged by the Service Control Manager with event ID 36871 which states:
A fatal error occurred while creating an SSL server credential. The internal error state is 10013.
In addition you may also see an error message logged by the Service Control Manager with event ID 7024 which states:
The SQL Server (ISARS) service terminated with service-specific error %%-2146893007.
This can occur when SSL 3.0 is disabled at the same time that TLS 1.0 is also disabled. Even though TLS 1.1 and 1.2 might be enabled, TMG requires that TLS 1.0 specifically be enabled for SQL server services to function properly when SSL 3.0 is disabled.
To resolve this issue, enable TLS 1.0 Server in the registry by changing the value of Enabled to 1, as shown here. If these registry keys do not exist, create them.
Restart the server for the change to take effect.
Mitigating the POODLE SSL 3 Vulnerability on Forefront TMG 2010
Recently a new and very serious vulnerability in the SSL 3.0 protocol has been discovered that allows an attacker to recover sensitive information for an encrypted session. The Qualys SSL Labs server test has been updated to identify and warn about this issue.
Figure 1 – Qualys SSL Labs Server Test Score for TMG Published Secure Web Site
On a Forefront TMG server with SSL hardening implemented as I’ve outlined here and here, the POODLE attack is mitigated, but it is still recommended that you disable SSL 3.0 altogether. SSL 3.0 is an old, outdated protocol that is no longer widely used, and disabling it should have minimal impact on clients connecting to secure web sites published by the Forefront TMG 2010 firewall.
To disable SSL 3.0 on the TMG firewall, open an elevated PowerShell window and execute the following commands:
New-Item -Path “HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server” -Force
New-ItemProperty -Path “HKLM:\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server” -PropertyType dword -Value 0 -Name Enabled
Note: Use caution when copying/pasting the above commands as wrapping of the text has occurred.
A restart of the server is required for the change to take effect.
Forefront TMG 2010 Network Inspection System NIS Signature Updates
When Microsoft announced the formal end-of-life for Forefront TMG 2010, they laid out in clear detail the support boundaries for the product going forward. Microsoft stated specifically that they would continue mainstream support for TMG until April of 2015, and extended support would terminate in April 2020. However, the Web Protection Service (WPS) updates for the URL filtering database, antimalware signatures, and the Network Inspection System (NIS) would only continue until December 31, 2015.
Unfortunately, it appears that Microsoft has abandoned the updating for NIS signatures. You may have noticed that a fully updated Forefront TMG firewall with the latest signature updates shows that the last NIS signature was released for security bulletin MS12-050 on July 20, 2012!
I find it difficult to believe that there hasn’t been a single vulnerability discovered or hotfix released since July of 2012 that wouldn’t benefit from NIS protection, so I have to assume that Microsoft is no longer supporting NIS in spite of their pledge to provide support for WPS through the end of 2015. If you are relying on NIS for essential network protection, it’s time to consider deploying a dedicated IDS/IPS solution or another solution that provides this functionality.
Recommended Forefront TMG 2010 SSL and TLS Configuration
Last year I wrote an article for ISAserver.org that provided detailed guidance for improving security for SSL and TLS protected web sites using Forefront TMG 2010. Many people have reached out to me recently to ask about enabling forward secrecy, which my original article did not include because, at the time, it was not recommended to enable it. However, as times have changed, it is now recommended to enable forward secrecy so I recently wrote a short post with guidance on how to do that. The post was written with a very narrow scope and addressed only the enabling of forward secrecy for TLS. Many of you have since asked for guidance on overall security best practices with regard to SSL and TLS along with adding support for forward secrecy. In addition to the configuration changes detailed in my original ISAserver.org article, I also recommend the following list of SSL and TLS cipher suites be explicitly enforced using the method outlined here.
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256_P256 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256_P384 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256_P521 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384_P384 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384_P521 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256_P256 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA_P256 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA_P256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P256 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA_P256 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA_P256 TLS_DHE_DSS_WITH_AES_128_CBC_SHA256 TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 TLS_DHE_DSS_WITH_AES_128_CBC_SHA TLS_DHE_DSS_WITH_AES_256_CBC_SHA TLS_RSA_WITH_AES_128_CBC_SHA256 TLS_RSA_WITH_AES_256_CBC_SHA256 TLS_RSA_WITH_AES_128_CBC_SHA TLS_RSA_WITH_AES_256_CBC_SHA
Using this configuration, the Forefront TMG 2010 firewall should receive an A rating from the SSL Labs test site (at the time of this writing).
Enabling and supporting the above list of cipher suites will provide the best overall protection and performance for your SSL protected web sites. Note that the list above does not include support for SSL 3.0. If you need to support SSL 3.0 you should add the following cipher suites to the end of the list.
TLS_RSA_WITH_RC4_128_SHA TLS_RSA_WITH_RC4_128_MD5
Please note that this configuration may not work with older browsers on old, unsupported operating systems, for example Internet Explorer 6 on Windows XP. Before deploying this configuration in production I would encourage you to conduct some testing with your supported clients to ensure operability.
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