Security & Cloud Computing
Switching the Locks: Who Has Copies of Your SSH Keys?
Organizations are constantly leaving themselves open to security breaches and noncompliance with federal regulations
By: Tatu Ylönen
Apr. 7, 2013 12:00 PM
Despite the recent flood of high profile network breaches, hacking attempts are hardly new. In 1995, I was attending school in Helsinki when I discovered a password "sniffer" attack in our university network. In response, I wrote a program called the "secure shell" to safeguard information as it traveled from point to point within the network. This new program shielded all of our data and ensured that these kinds of attacks didn't jeopardize our logins.
This program, SSH, works by developing an encryption key pair - one key for the server and the other key for the user's computer - and encrypting the data that is transferred between those two keys. Currently, almost every major network environment - including those in large enterprises, financial institutions and governments - uses a version of SSH to preserve data in transit and let administrators operate systems remotely. Organizations use SSH to encrypt everything from health records to logins, financial data and other personal information.
Management of Keys a Low Priority
Organizations are constantly leaving themselves open to security breaches and noncompliance with federal regulations by not being more diligent about SSH key management. Many are incapable of controlling who creates keys, how many are created, or where they are positioned in the network after being dispensed and those discrepancies will lead them to network-wide attacks.
Swept Under the Rug
SSH key mismanagement is as mysterious as it is widespread. Through dialogs with prominent governments, financial institutions and enterprises, we have determined that on average most companies have between eight and over 100 SSH keys in their environments that allow access to each Unix/Linux server. Some of these keys also permit high-level root access, allowing servers to be vulnerable to "high-risk" insiders. These "insiders," including anyone who has ever been given server access, can use these mismanaged SSH keys to gain permanent access to production servers.
Mismanaged SSH Keys Give Viruses the Advantage
Key-based access networks are so closely connected that it is extremely likely that a successful attack will travel through all organizational servers, especially if the virus also uses additional attack vectors to increase privileges to "root" after breaching a server. With the high number of keys being distributed, it is likely that the virus will infect nearly all servers within minutes, including disaster recovery and backup servers that are typically also managed using such keys.
In the worst case scenario, a virus utilizing numerous attack vectors could spread Internet-wide, rapidly and, combined with dissolution technologies, could corrupt enormous quantities of data.
Industry Regulations Flouted
The SSH protocol and its most commonly used implementations do not create these risks. Rather, it is the result of faulty protocols relating to SSH keys, inadequate time and means to research the problem to develop solutions, lack of understanding of the implications of the issue and the hesitancy of auditors to flag problems that they do not have solutions for.
Clearly the issue of SSH keys being improperly managed cannot be glossed over forever. Without auditing, controlling, or terminating SSH key-based access to their IT systems and data properly, most healthcare providers, enterprises and government agencies are easy targets for an attacker.
Steps to Combat the Risks
There are multiple steps that make up the core of the remediation project:
The Future of Security
Nearly all of the Fortune 500 and several prominent government agencies are inadvertently putting themselves at risk to major security threats from hackers or rogue employees because they continue to operate out of compliance. This problem cannot be solved overnight. It will take numerous years and thousands of well-trained people to fully combat the problem. It must be the entire organization's responsibility to address the issue. Time must be allotted and it must become a priority to ensure that SSH user keys are properly managed in their companies.
Reader Feedback: Page 1 of 1
SOA World Latest Stories
Subscribe to the World's Most Powerful Newsletters
Subscribe to Our Rss Feeds & Get Your SYS-CON News Live!
SYS-CON Featured Whitepapers
Most Read This Week