Mozilla, Google, Apple block compromised eMudhra CA certificates

Researchers identified that eight intermediate certificates issued by the certificate authority eMudhra had private keys so weak that attackers could recover them almost instantly. This weakness enables attackers to forge trusted certificates for legitimate websites, undermining the trust model of TLS/SSL. In response, eMudhra revoked the affected intermediate certificates, and major browser vendors such as Mozilla, Google, and Apple have blocked these certificates to protect users from potential man-in-the-middle attacks or impersonation.

The compromised intermediate certificates could allow attackers to issue fraudulent certificates trusted by browsers, potentially enabling man-in-the-middle attacks or impersonation of legitimate websites. This undermines the security of TLS connections relying on these certificates. However, the revocation and blocking by major browsers mitigate the risk of exploitation.

The affected intermediate certificates have been revoked by eMudhra, and major browsers have blocked them. Users and administrators should ensure their systems do not trust these revoked certificates. No further action is required if browsers and systems are up to date and respect certificate revocation lists and browser blocklists.