Google to revoke trust in a Symantec root certificate
15 December 2015 | 0
In an alert, the company said that as of 1 December it no longer was using the root certificate, which is trusted by default in most browsers and operating systems, to issue TLS/SSL or code signing certificates.
The company advises owners of digital certificates that chain back to the Class 3 Public Primary CA to obtain new ones that link back to a more modern root. Such replacement certificates are available for free.
According to Google, Symantec will not completely kill off the Class 3 Public Primary CA root and intends to use it for new, unspecified purposes. Because of this, the browser maker cannot guarantee that non-public certificates issued under this root in the future won’t be used to “intercept, disrupt, or impersonate the secure communication of Google’s products or users”.
“As Symantec is unwilling to specify the new purposes for these certificates, and as they are aware of the risk to Google’s users, they have requested that Google take preventative action by removing and distrusting this root certificate,” said Ryan Sleevi, a Google software engineer, in a blog post.
The company will remove two versions of the Class 3 Public Primary CA certificate from its products’ trust lists. One version is signed with SHA-1, a hashing algorithm that is in the process of being phased out, and one is signed with MD2, an even older hashing function. Both versions were issued in 1996 and are set to expire in 2028.
According to Google, Symantec doesn’t believe that any of its customers who operate HTTPS websites, or their users, will be impacted. However, in its own advisory Symantec acknowledges that users might receive errors in the future if they try to access websites whose certificates chain back to the distrusted root.
This might also happen with signed applications if OS makers also start removing the Class 3 Public Primary CA certificate from their trust lists. Therefore developers should also change their certificates if their chain back to this root and re-sign their code.
Symantec notified all major browser vendors in November to remove the VeriSign Class 3 Public Primary Certification Authority G1 (PCA3-G1) from their trust lists because it is based on older and lower strength security than currently recommended, Symantec spokesman Noah Edwardsen said via e-mail. The root certificate hasn’t been used to generate new certificates in several years and the company’s scans confirmed that it’s removal poses no risk to the public Internet, he said.
Edwardsen also clarified the certificate’s new purpose, saying that it will be used “to provide transition support” for some of Symantec’s enterprise customers’ “legacy, non-public applications”.
“By announcing that they will be blocking this root certificate, Google has indicated that they intend to do exactly as we requested, a step that other browsers started taking in 2014,” the Symantec spokesman said.
Lucian Constantin, IDG News Service