1024-bit RSA cracked!

RSA encryption is the cornerstone of public-key cryptography, and for decades, 1024-bit encryption was believed to be "uncrackable." For example, over 95% of SSL certificates currently in production on the Internet are 1024-bit. Only recently have SSL registrars encouraged (or required) that certificates use 2048-bit or higher (up to 4096-bit) keys, saying that the growth of computing power meant that it was only a matter of time until 1024-bit security was compromised. It seems that their predictions have come true.

The crack was completed in roughly 100 hours with a cluster of Pentium-4 servers and left no trace on the system to show that it had ever been carried out. While this rules out a large number of scenarios, it doesn't rule out any situation where an individual has physical access to the power being delivered to a system. If you think that it's not possible, look at the ratio between risk versus reward for some targets. How valuable would it be for someone to spoof Amazon's SSL certificate, or Paypal's? The cluster can be built up and torn down in any cloud environment. A low-level datacenter technician now qualifies as a potential attacker. All of the physical and network security that goes into protecting your environment can be nullified by an uncontrolled variable - those who have access to the power being delivered to your systems.

Rather than stay up all night worrying about Charlie the Janitor, we recommend that you focus on upgrading your security. No more 1024-bit keys for SSL, GPG, or other encryption. SSL keys should be 2048-bit or higher. Personal encryption keys (SSH, GPG and those that assert that you are who you say you are) should be 4096-bit. This will protect you for the foreseeable future, but eventually, even they will fall.