Nearly three-quarters of the Global 2000 continue to be vulnerable to attack because they have not fully hardened their systems against the effects of the OpenSSL Heartbleed vulnerability reported a year ago, key-management firm Venafi stated in a report released on April 7.
Using scans of Global 2000 companies' public-facing systems, the firm found that 74 percent of the businesses are still vulnerable to the fraudulent use of encryption and certificate keys stolen in the days following the disclosure of the Heartbleed vulnerability. Eight months ago, 76 percent of companies were vulnerable, Venafi reported.
While companies have patched the OpenSSL software that contained the original vulnerability, attackers had used Heartbleed to harvest the Secure Sockets Layer (SSL) keys and certificates of vulnerable Web sites, virtual private networks and other services. Those certificates and keys are still being used by more than 1,200 companies in the Global 2000, leaving them vulnerable to future attacks, Kevin Bocek, vice president of security strategy and threat intel at Venafi, told eWEEK.
"Would I want my private keys out in people's hands, still being able to be used?" he said. "I don't think anyone would say that they would want to be in that position. That is the whole reason that we have these keys to begin with."
On April 7, 2014, the OpenSSL Project reported that a vulnerability in its widely used implementation of the Secure Sockets Layer (SSL) protocol could allow attackers to remotely retrieve sensitive data from servers using a common feature of the software. Using a simple attack, researchers were able to show that passwords, secure data and private cryptographic keys could all be retrieved remotely.
The most popular Websites and services patched the software quickly. Within 48 hours of disclosure, for example, the vulnerable servers in the Alexa Top 500 list of Websites had updated their OpenSSL software, a group of researchers from four respected universities stated in an academic paper on the response to Heartbleed. However, attackers were even quicker to take advantage of the vulnerability. Within 24 hours of the disclosure, the researchers detected scans emanating from more than 700 sources across the Internet, suggesting widespread attempts to identify vulnerable servers.
To what degree attackers recovered the private keys from major companies is unknown. However, keys recovered through Heartbleed allowed attackers to breach health care provider Community Health Systems in August and steal more than 4.5 million records, according to security firm TrustedSec. The firm's analysis relied on statements from three anonymous sources familiar with the CHS investigation, but CHS has never denied the assertion.
In addition, an uptick in attacks on health care companies and hospitals can be blamed on the Heartbleed vulnerability, according to security firm Websense.
To completely harden their systems, companies have to track down all the keys and certificates that might have been exposed in the time between the disclosure of Heartbleed and when the firm patched its servers. A company must then, not just reissue new certificates, but generate a new private key, Venafi said.
The problem is that security and application administrators "will go ahead and reissue certificates, but not create a new key and make a new certificate request off that key," Bocek said.
Of the Fortune 2000, 1,639 companies have systems that were vulnerable to Heartbleed, and 1,223—or 74 percent—have not completely remediated the issue, as of April 2015. According to a Ponemon Institute survey, more than 40 percent of Fortune 2000 companies in the United States and Germany believe themselves to have remediated the issue, while less than 15 percent of firms in Australia, and a quarter of firms in France, make the same claim.