SSL certificates for the .google.com domain are forged
Unknowns managed to unauthorizedly obtain a valid certificate for .google.com. This makes it possible to conduct attacks MITM against users of Google services. The certificate was issued by the Dutch certification center DigiNotar and has now been withdrawn. Google Chrome users are not at risk as it checks the validity of certificates online. Mozilla Firefox have released an update and recommend manually disabling the DigiNotar certificate in the browser settings.
Microsoft has released a security bulletin and an update that removes the DigiNotar root certificate from the Microsoft Certificate Trust List.