SHA-1 Security Certificate Vulnerability

03/26/2020 22 12604

DESCRIPTION:

As of January 1st, 2017, Certificate Authorities have unanimously stopped using SHA-1 certificates. This will result in browsers rejecting SHA-1 certificates. Any code which is signed after January 1st, 2016, is no longer trusted by Microsoft. Firmware versions prior to 5.8.4.0 do not support SHA-2 cryptographic hashing.

This means that any SonicWall UTM appliances running this older firmware will experience issues with connecting to any sites which no longer use SHA-1. The main scope of impact for our appliances is their ability to securely connect to our sites for licensing and signature downloads, as we have also abandoned the use of SHA-1 certificates for our sites and services.

In summary:

• Every 3rd generation SonicWall firewall is affected and vulnerable.
• Every 4th generation SonicWall firewall is affected and vulnerable.
• Every 5th generation SonicWall firewall running firmware newer than 5.6.x, but older than 5.8.4.x will not be able to manage licensing from the firewall.
• Every 5th generation SonicWall firewall running firmware equal to 5.8.4.0 or newer will not be affected.
• 6th generation NSA 2600 on firmware older than 6.1.2.6 are affected and vulnerable.
• All other 6th generation devices on firmware versions older than 6.1.1.12 are affected and vulnerable.
• Gen 6 devices running 6.2.5.3 are not affected.
  

RESOLUTION:
If you are using an older 5th generation SonicWall firewall, and that firewall is running 5.8.x firmware, it is recommended that you upgrade your firmware or upgrade to a 6th generation appliance. The driving factor behind this recommendation is that the 5.8.x firmware is known to contain vulnerabilities and limitations with regards to SHA-1 certificates. The main concern is that if enough computing resources are employed, attackers could conceivably generate fake certificates and install them to various endpoints on the Internet.

Appliance Upgrades
At this point, all customers are strongly advised to upgrade all older firewalls to a comparable 6th generation SonicWall UTM appliance under the Customer Advantage Program (Secure Upgrade Plus offer). If you require any assistance with upgrading your appliance to 6th generation hardware, please contact your preferred SonicWall reseller.

Firmware Upgrades
If you are unable to upgrade to a 6th generation appliance at this time, it is recommended that all customers upgrade all internal and external Certificate Authorities to SHA-2, and that all 5th generation appliances are running 5.8.4.0 or newer and all 6th generation appliances are running 6.2.5.3.

Preferably, all 5th generation appliances should be running 5.9.1.7, as this is our latest general release to date for 5th gen hardware.

For more information on how to upgrade your appliance, please see our article Procedure to upgrade the SonicWall firmware Image with Current Preferences