For many years, Mozilla, NIST, the CA/Browser Forum, and others have been encouraging Certification Authorities (CAs) to upgrade their 1024-bit RSA keys to a stronger cryptographic algorithm (either longer RSA keys or ECDSA). We are actively working with CAs to & Continue reading

https://blog.mozilla.org/security/2014/09/08/phasing-out-certificates-with-1024-bit-rsa-keys/