From: EFF
Iranian hackers obtain fraudulent HTTPS certificates: How close to a Web security meltdown did we get?
On March 15th, an HTTPS/TLS Certificate Authority (CA) was tricked into issuing fraudulent certificates that posed a dire risk to Internet security. Based on currently available information, the incident got close to – but was not quite – an Internet-wide security meltdown. These events show why we urgently need to start reinforcing the system that is currently used to authenticate and identify secure websites and email systems.