In a threat bulletin published on our blog in December, we explored the details of the major breach at Sony Pictures Entertainment orchestrated by the “Guardians of Peace” (also known as #GOP). The attack resulted in the release of much more than gigabytes of valuable data, including dozens of digital certificates and SSH and SSL private keys—keys that could allow privileged-user access to the entire internal network of Sony. Once on the network, using these compromised keys, the bad guys likely remained undetected for weeks, months, or even years and had unfettered access to systems and data. And now that these private keys are in the wild, more bad guys could further infiltrate Sony.
Since the news initially broke there have been multiple updates and discoveries, and I suspect there will continue to be more. This is a huge, complex breach that would have been very difficult to stop—but within it are a few important lessons for other enterprises to take to heart.
- The threatscape has changed. Cybercriminals are (and have been) looking to compromise cryptographic keys and certificates, and this Sony breach is just the latest in a series of several incidents using the same exploit. Looking back to April 2011, Sony’s PlayStation Network (PSN) suffered a significant breach that exposed names, addresses, and credit card data belonging to 77 million user accounts and shut down the PSN for several weeks. The breadth of the data exposed in that attack indicated that data which should have been encrypted was not.
- Incident response must involve replacing all key and certificates. The incidents at Sony should sound familiar: we’ve seen cybercriminals from Mask, Crouching Yeti, APT18 and others misuse SSL certificates and SSH keys. In these cases and others, attackers can gain unauthorized access to a system with elevated privileges using a compromise certificate or SSH key (like Edward Snowden), expand their attack by gaining more data or misusing a compromised system, gain access to continually more systems, and leave behind backdoors as we’ve seen with Shellshock.
- This is another clear example proving keys and certificates must be secured and protected. Here’s a case of history doomed to repeat itself as long as the same attack pattern continues to work (and it does): get the keys and own the kingdom. As recent breaches have proved—and as the Cost of Failed Trust research revealed almost two years ago—all it takes is one compromised key or vulnerable certificate to cause millions of dollars in damages. Failing to continuously surveil all keys and certificates, enforce a policy, detect misuse and anomalies, and respond and remediate by replacing them with good keys and certificates means that security will continue to be undermined. By misusing keys and certificates bad actors can undermine and circumvent many of the most critical security controls, including strong authentication, DLP, sandboxing and privileged access management.
So while many IT security pros and incident response teams continue to focus on who was behind the Sony breach, what their intention was, and what data was stolen or exposed, let’s take this opportunity to learn an important lesson. We should start 2015 by working to better secure and protect SSL keys and certificates, SSH keys, and the range of keys and certificates increasingly being used for VPN, WIFI, and MDMs.