Why Migrate to SHA-2 SSL Certificates?
As your security partner, DigiCert has already made SHA-256 the default for all new SSL Certificates issued, and strongly recommends that all customers update their SHA-1 certificates to SHA-2.
Cryptanalysts have urged administrators to replace their SHA-1 certificates as the risks associated SHA-1 are greater than previously expected. While there doesn’t appear to be an immediate present danger, we strongly encourage administrators to migrate to SHA-2 as soon as feasibly possible.
Quickly Find and Replace SHA-1 CertificatesDiscovery Cloud helps you quickly find and replace SHA-1 SSL Certificates with a free DigiCert SHA-2 certificate.

When Should I Switch to SHA-2?
Google, Mozilla, and Microsoft have already started phasing out trust for SHA-1 SSL Certificates. Chrome shows SHA-1 warnings for sites using SHA-1 certificates. Administrators who have not yet replaced their SHA-1 certificates with SHA-2 certificates should start making the switch now.
In November 2013, Microsoft announced that it would stop trusting SHA-1 certificates due to concerns that the algorithm is no longer secure. It stated that the deadlines in the SHA-1 deprecation policy reflected their estimation of the likelihood of the threat from SHA-1 attacks. Mozilla has announced a similar timeline for its products.
In August 2014, Google took an even more aggressive stance stating that Chrome will display warnings starting in November 2014 for sites secured with SHA-1 certificates due to SHA-1 being insufficiently secure. Google’s intent is to help phase out SHA-1 certificates on an accelerated timeline and make the transition smoother than MD5.
In October 2015, an international team of cryptanalysts published research urging administrators to replace their SHA-1 certificates sooner as the risks associated SHA-1 are greater than previously expected. The published findings are theoretical and have not yet been proven in a practical setting. While there doesn't appear to be an immediate danger, we strongly encourage administrators to migrate to SHA-2 as soon as possible.
Administrators should consider the impact this update could have and plan for the following:
- Hardware compatible with SHA-2
- Server software updates supporting SHA-2
- Client software support for SHA-2
- Custom application support for SHA-2
Browsers and CAs have previously encouraged migration to SHA-2 by 2017, however current research should encourage organizations to accelerate their plans to upgrade existing infrastructure to support SHA-2. For more information about SHA-2 timelines, please visit our SHA-2 FAQ.