Comprehensive cybersecurity is an unfortunate necessity in the connected age, as malwares like Duqu, Flame, and Stuxnet have proven to be effectiveinstruments of espionage and physical sabotage rather than vehicles of petty cybercrime. In an effort to mitigate the impact of such threats on United States Critical Infrastructure (CI), the Department of Homeland Security (DHS) developed the Enhanced Cybersecurity Services (ECS) program, a voluntary embedded system framework designed to augment the existing cyber defenses of CI entities. The following provides an overview of the ECS program architecture, technology, and entry qualifications as described in an “on background” interview with DHS embedded pc officials.
At some point in 2007, an operator at the Natanz uranium enrichment facility in Iran inserted a USB memory device infected with the Stuxnet malware into an Industrial Control System (ICS) running a Windows Operating System. Over the next three years, the embedded system would propagate over the Natanz facility’s internal network by exploiting zero-day vulnerabilities in a variety of Windows OSs, eventually gaining access to the Programmable Logic Controllers on a number of Industrial Control Systems (PCSs) for the facility’s gas centrifuges. Stuxnet then injected malicious code to make the centrifuges spin at their maximum degradation point of 1410 Hz. One thousand of the 9,000 centrifuges at the Natanz facility were damaged beyond repair.
In February 2013, Executive Order (EO) 13,636 and Presidential Policy Directive (PPD)-21 ordered the DHS to develop a public-private partnership model to protect United States CI entities from cyber threats like Stuxnet. The result was an expansion of the Enhanced Cybersecurity Services (ECS) program from the Defense Industrial Base (DIB) to 16 critical industrial pc.
Enhanced Cybersecurity Services framework
At its core, the embedded system pc is a voluntary information-sharing framework that facilitates the dissemination of government-furnished cyber threat information to CI entities in both the public and private sectors. Through the program, sensitive and classified embedded system information is collected by agencies across the United States Government (USG) or EINSTEIN sensors1 placed on Federal Civilian Executive Branch (FCEB) agency networks, and then analyzed by DHS to develop “threat indicators”. DHS-developed threat indicators are then provided to Commercial Service Providers (CSPs)2 that, after being vetted and entering a Memorandum of Agreement (MOA) with DHS, may commercially offer approved ECS services to entities that have been validated as part of United States CI. The ECS services can then be used to supplement existing cyber defenses operated by or available to CI entities and CSPs to prevent unauthorized access, exploitation, and data exfiltration.
In addition, CSPs may also provide limited, anonymized, and industrial cybersecurity metrics to the DHS Office of Cybersecurity & Communications (CS&C) with the permission of the participating CI entity. Called Optional Statistical Information Sharing, this practice aids in understanding the effectiveness of the ECS program and its threat indicators, and promotes coordinated protection, prevention, and responses to malicious cyber threats across federal and commercial domains.
Enhanced Cybersecurity Services countermeasures the initial implementation of ECS, including two countermeasures for combating cyber threats: Domain Name Service (DNS) sinkholing and embedded pc e-mail filtering.
DNS sinkholing technology is particularly effective against malwares like Stuxnet that are equipped with distributed command and control network capabilities, which allows threats to open a connection back to a command and control server so that its creators can remotely access it, give it commands, and update it. The DNS sinkholing capability enables CSPs to prevent communication with known or suspected malicious Internet domains by redirecting the network connection away from those domains. Instead, CSPs direct network traffic to “safe servers” or “sinkhole servers,” both hindering the spread of the malware and preventing its communications with embedded pc cyber attackers.
The e-mail filtering capability is effective in combating cyber threats like Duqu, for example, which spread to targets through contaminated Microsoft Word e-mail attachments (also known as phishing), then used a command and control network to exfiltrate data encrypted in image files back to its creators. The e-mail filtering capability enables CSPs to scan attachments, URLs, and other potential malware hidden in e-mail destined for an entity’s networks and potentially quarantine it before delivery to end users.
Accreditation and costs for Enhanced Cybersecurity Services
The CS&C is the DHS executive agent for the ECS program, and executes the CSP security accreditation process and MOAs, as well as validation of CI entities. Any CI entity from one of the 16 key infrastructure sectors can be evaluated for protection under the ECS program, including state, local, tribal, and territorial governments.
For CSPs to complete the security accreditation process, they must sign an MOA with the USG that defines ECS expectations and specific program activities. The MOA works to clarify the CSP’s ability to deliver ECS services commercially while adhering to the program’s security requirements, which include the ability to:
Accept, handle, and safeguard all unclassified and classified indicators from DHS in a Sensitive Compartment Information Facility (SCIF) Retain employee(s) capable of holding classified security clearances for the purposes of handling classified information (clearance sponsorship is provided by DHS)
Implement ECS services in accordance with security guidelines outlined in the network design provided on signing of the embedded pc versions of MOA.
Privacy, confidentiality, and Enhanced Cybersecurity Services
“ECS does not involve government monitoring of private communications or the sharing of communications content with the government by the CSPs,” a DHS official told Industrial embedded systems. Although CSPs may voluntarily share limited aggregated and anonymized statistical information with the government under the ECS program, ECS related information is not directly shared between customers of the CSPs and the government.
“CS&C may share information received under the ECS program with other USG entities with cybersecurity responsibilities, so long as the practice of sharing information is consistent with its existing policies and procedures. DHS does not control what actions are taken to secure private networks or diminish the voluntary nature of this effort. Nor does DHS monitor actions between the CSPs and the CI entities to which they provide services. CI entities remain in full control of their data and the decisions about how to best secure it.”