Free certificate authority Let s Encrypt said it will revoke 3 million Transport Layer Security (TLS) certificates Wednesday. The move could mean that millions of websites and machine identities that rely on those certificates to protect sensitive data flow could be identified as insecure, or rendered unavailable. The actual number of websites or machine identities affected will likely be less, because of the way certificates are reissued and the fact that others are likely not currently in use, said Pratik Savla, senior security engineer at Venafi.
Source: https://threatpost.com/lets-encrypt-revoke-millions-tls-certs/153413/