Trailrunner7 writes: Google security engineers, investigating fraudulent certificates issued for several of the company's domains, discovered that a Chinese certificate authority was using an intermediate CA, MCS Holdings, that issued the unauthorized Google certificates, and could have issued certificates for virtually any domain. Google's engineers were able to block the fraudulent certificates in the company's Chrome browser by pushing an update to the CRLset, which tracks revoked certificates. The company also alerted other browser vendors to the problem, which was discovered on March 20. Google contacted officials at CNNIC, the Chinese registrar who authorized the intermediate CA, and the officials said that they were working with MCS to issue certificates for domains that it registered. But, instead of simply doing that, and storing the private key for the registrar in a hardware security module, MCS put the key in a proxy device designed to intercept secure traffic.