Since the dawn of time humanity has needed to protect both people and things. Initial security methods were all “software based” in the sense that they relied on the user putting their trust in a process, people and social conventions. At first, it was cavemen hiding what they most valued, leveraging security through obscurity or they posted a trusted associate to watch the entrance. Finally, we expanded our security methods to include some form of “Keep Out” signs through writings and carvings. Then in 600BC along comes Theodorus of Samos, who invented the key. Warded locks had existed about three hundred years before Theodorus, but the “key” was just designed to bypass obstructions to its rotation making it slightly more challenging to access the hidden trip lever inside. For a Warded lock the “key” often looked like what we call a skeleton key today.
It could be argued that the lock represented our first “hardware based” security system as the user placed their trust in a physical token or key based system. Systems secured in hardware require that the user present their token in person, it is then validated, and if it passes, the security measures are removed. It should be noted that we trust this approach because it’s both the presence of the token and the accountability of a person in the vicinity who knows how to execute the exact process with the token to ensure success.
Now every system man invents can also be defeated. One of the first skills most hackers teach themselves is how to pick a lock. This allows us to dynamically replicate the function of the key using two very simple and compact tools (a torsion bar and a pick). Whenever we pick a lock we risk exposure, something we avoid at all cost, because the process of picking a lock looks visually different than that of using a key. Picking a lock using the tools mentioned above requires two hands. One provides a steady rotational force using the torsion bar. While the other manipulates the pick to raise the pins until each aligns with the cylinder and hangs up. Both hands require a very fine sense of touch, too heavy handed with the torsion bar and you can snap the last pin or two while freeing the lock. This will break it for future key users, and potentially expose your attempted tampering. Too light or heavy with the pick and you won’t feel the pins hanging up, it’s more skill than a science. The point is that while using a key takes seconds picking a lock takes much longer, somewhere between a few seconds to well over a minute, or never, depending on the complexity of the cylinder, and the person’s skill. The difference between defeating a software system and a hardware one is typically this aspect of presence. While it’s not always the case, often to defeat hardware-based systems it requires that the attacker be physically present because defeating hardware commonly requires hardware. Hackers often operate from countries far outside the reach of law enforcement, so physical presence is not an option. Attackers are driven by a risk-reward model, and showing up in person is considered very high risk, so the reward needs to be exponentially greater.
Today companies hide their most valuable assets in servers located in large secure data centers. There are plenty of excellent real-world hardware and software systems in place to ensure proper physical access to these systems. These security measures are so good that hackers rarely try to evade them because the risk of detection and capture is too high. Yet we need only look at the past month, April 2019, to see that companies like Microsoft, Starwood, Toyota, GA Tech and Questcare have all reported breaches. In Microsoft’s case, 6% of all MSN, HotMail, and Outlook accounts were breached, but they’ve not disclosed the details or the number of accounts. This is possible because attackers need to only break into a single system within the enterprise to reach the data center and establish a beachhead from which they can then land and expand. Attackers usually obtain a secure foothold through a phishing email or clickbait.
It takes only one undereducated employee to open a phishing email in outlook, launch a malicious attachment, or click on a rogue webpage link and it’s game over. Lockheed did extensive research in this area and they produced their now famous Cyber Kill Chain model. At a high level, it highlights the process by which attackers seize control of an enterprise. Anyone of these attack vectors can result in the installation of a remote access trojan (RAT) or a Zero-Day exploit that will give the attacker near unlimited access to the employee’s system. From there the attacker will seek out a poorly secured server in the office or data center to establish a beachhead from which they’ll launch their attack. The compromised employee system may not always be available, but it does makes for a great point to retreat back to in the event that the primary beachhead server system is discovered and sanitized.
Once an attacker has a foothold in the data center its game over. Very often they can easily move laterally, east-west, through the data center to other systems. The MITRE ATT&CK (Adversarial Tactics Techniques & Common Knowledge) framework, while similar to Lockheed’s approach, drills down much further. Specifically, on the lateral movement strategies, Mitre uncovered 17 different methods for compromising internal servers. This highlights the point that very few defenses exist in the traditional data center and those that do are often very well understood by attackers. These defenses are typically OS based firewalls that all seasoned hackers know how to disable. Hackers will disable logging, then tear down the firewall. They can also sometimes leverage an island hopping attack to a vendor or customer systems through private networks or gateways. Or in the case of the Starwood breach of Marriott the attackers got lucky and when their IT systems were merged so were the exploited systems. This is known as a data lemon, an acquisition that comes with infected and unsecured systems. Also, it should be noted that malicious insiders, employees that are aware of a pending termination or just seeking to augment their income, make up over 30% of the reported breaches. In this attack example, a malicious insider simply leverages their access and knowledge to drain all the value from their employer’s systems. So what hardware countermeasures can be put in place to limit east-west or lateral attacks within the data center? Today you have three hardware options to secure your data center servers against east-west attacks. We have switch access control lists (ACLs), top of rack firewalls or something uniquely innovative Solarflare’s ServerLock enabled NICs.
Often enterprises leverage ACLs in their top of rack 10/25/100G switches to protect east-west traffic within the data center. The problem with this approach is one of scale. IT teams can easily exhaust these resources when they attempt comprehensive application level segmentation at the server. These top of rack switches provide between 100 and 1,000 ACLs per port. By contrast, Solarflare’s ServerLock provides 5,000 ACLs per NIC, along with some foundational subnet level filtering.
In extreme cases, companies might leverage hardware firewalls internally to further zone off systems they are looking to secure. Here the problem is one of volume. Since these firewalls are used within the data center they will be tasked with filtering enormous amounts of network data. Typically the traffic inside a data center is 10X the traffic volume entering the data center. So for mission-critical clusters or server groups, they will demand high bandwidth, and these firewalls can become very expensive and directly impact application performance. Some of the fastest appliance-based firewalls designed to handle these kinds of high volumes are both expensive and add another 2.5 to 3.5 microseconds of latency in each direction. This means that if an intranet server were to fetch information from a database behind an internal firewall the transaction would see an additional delay of 5-6 microseconds. While this honestly doesn’t sound like much think of it like compound interest. If the transaction is simple and there’s only one request, then 5-6 microseconds will go unnoticed, but what happens when that employee’s request decomposes into hundreds or even thousands of database server calls? Delays then become seconds. By comparison, Solarflare’s ServerLock NIC based ACL approach adds only 0.25 to 0.75 microseconds of latency in each direction.
Finally, we have Solarflare’s ServerLock solution which executes entirely within the hardware of the server’s own Network Interface Card (NIC). There are NO server side services or agents, so there is no attackable software surface area of any kind. Think about that for a moment, a server-side security solution with ZERO ATTACKABLE SURFACE AREA. Once ServerLock is engaged through the binding process with a centralized ServerLock DirectorOne controller the local control plane for the NIC that manages security is torn down. This means that even if a hacker or malicious insider were to elevate their privilege to root they would NOT be able to see or affect the security settings on the NIC. ServerLock can test up to 5,000 ACLs against a network packet within the NIC in just over 250 nanoseconds. If your security policies leverage subnet wildcards the worst case latency is under 750 nanoseconds. Both inbound and outbound network traffic is checked in hardware. All of the Solarflare NICs within a data center can be managed by ServerLock DirectorOne controllers. Today a single ServerLock DirectorOne can manage up to 1,000 NICs.
ServerLock DirectorOne is a bundle of code that is delivered as an ISO image and can be installed onto a bare metal server, into a VM or a container. It is designed to manage all the ServerLock NICs within an infrastructure domain. To engage ServerLock on a system you run a simple binding process that facilitates an exchange of secrets between the DirectorOne controller and the ServerLock NIC. Once engaged the ServerLock NIC will begin sharing new network flows with the DirectorOne controller. DirectorOne provides visibility to all the network flows across all the ServerLock enabled systems within your infrastructure domain. At that point, you can then begin defining security policies and place them in compliance or enforcement mode. In compliance mode, no traffic through the NIC will be filtered, but any traffic that is not in compliance with the defined security policies for that NIC will generate alerts. Once a policy is moved into “enforcement” mode all out of policy packets will have the default action applied to them.
If you’re looking for the most secure solution to protect your companies servers you should consider Solarflare’s ServerLock. It is the most affordable, and secure way to protect your valuable corporate assets.