Healthcare beware: Crypto-mining, malware, and IoT attacks

Dave Palmer, Director of Technology, Darktrace | Monday August 20, 2018

In the past year, the healthcare industry has been increasingly targeted by advanced cyber-attacks. While a marked rise in medical IoT devices has allowed healthcare companies to become much more efficient, this increase has also opened new avenues for threat actors attempting to infiltrate their networks.

Medical staff now carry multiple connected devices with them, including personal devices that lack appropriate security controls. Confidential patient records and life-critical medical systems run an increased risk of being compromised, and the sensitive nature of the information they contain could impact patient safety and hospital reputation. Financially, healthcare companies are also at greater risk: according to a study by the Ponemon Institute, lost or stolen healthcare records can cost up to 136% more than data breached in other industries.

Going for gold

Towards the end of last year, we observed a noticeable spike in the number of crypto-mining infections within the healthcare sector. In December 2017 alone, the number of crypto-malware attempts on healthcare customers’ systems was 800% higher than in the six months prior and following.

Whilst healthcare companies have always been the target of malware infections, the sudden increase in crypto-malware was significant. This could be attributed to the price of Bitcoin and similar cryptocurrencies skyrocketing around the same time. As their price has now fallen, so have the crypto-mining attempts.

Breaking through Windows

Although 2018 brought with it a decrease in crypto-mining attempts, the healthcare sector experienced an increase in active malware infections captured by sinkhole domains. The infections were varied, with no bias towards botnets, trojans, or ransomware, but were almost entirely united in that the threat actors widely targeted outdated Windows operating systems.

The risks of the EternalBlue SMB vulnerability are now well known. However, as learnt in the aftermath of WannaCry, entire NHS trusts are also susceptible to other unpatched Windows 7 vulnerabilities, including those that facilitate remote code execution and privilege escalation – prime pickings for any malware that successfully enters a system.

Hiding in plain sight

A private medical institution recently trialed Darktrace’s Enterprise Immune System technology through a Proof of Value. Darktrace immediately discovered that an AXIOS spectrometer, a medical IoT device for characterizing materials using x-ray, had been compromised. It had breached hundreds of models, many of a potentially serious nature. The device was continuously making outbound SSH connections to rare external IP addresses, transferring over 1GB of data a week.

Further analysis determined that the compromised medical device was being used to send large volumes of outbound spam mail, resulting in the medical institution’s external IP address being blocked by spam filters. Effectively classified as a sender of junk mail, emails from the medical institution risked falling into recipients’ trash or not being received at all – anything from appointment updates, to the results of cancer scans. Faith in the institution’s ability to handle patient data and uphold its duty of care could have been severely undermined, risking its reputation among prospective patients and service providers.

An AXIOS spectrometer.

Likely C2 beaconing was also noted from this device, indicating that it might have been part of a wider botnet, or network of compromised devices being used to propagate malicious spam malware. On further investigation, at least one of the HTTP connections was to a server utilized within cryptocurrency exchange and bitcoin activity, which suggests a crypto-mining malware presence. The institution’s security team were advised immediately. The device was then isolated, giving the team precious time to conduct further investigation.

What next?

The healthcare sector is a clear target for threat actors, especially considering the wealth of sensitive data such networks safeguard, and the security holes left open in the challenge to continuously maintain and patch highly complex and distributed networks. WannaCry and Petya ransomware were unlikely to have been the last aggressive attacks that successfully exploit such vulnerabilities.

Insider threat is also manifest in healthcare networks. User compliance problems are prevalent, for example, there is a sizable use of Tor as the preferred VPN, widespread use of BitTorrent, and a high volume of illicit uploads to cloud storage services.

Darktrace’s technology has the unique ability to detect and respond to in-progress cyber-attacks that would ordinarily bypass traditional security tools. As threat actors are continually employing novel methods to compromise a network, a growing number of healthcare companies are now having to play catch-up in a fast-evolving threat landscape.

Trusting the cloud: Unencrypted data upload by government body

Max Heinemeyer, Director of Threat Hunting | Monday July 16, 2018

Managing misconceptions

As the market increasingly moves to the next wave of computing models, over 90% of organizations are expected to adopt hybrid infrastructures by 2020. This move to the cloud brings undeniable benefits for most organizations - from start-ups looking for minimal up-front costs to large organizations striving to boost efficiency, scale on demand, and benefit from constant availability of services and increased agility.

Alongside this growth, the challenge of securing critical data in the cloud has taken on a new dimension. As internal servers are so commonly affected by malware infections or insider threats, there exists a common misconception that the data stored within the cloud is somehow more secure than the data resting on company fileservers. However, this is not necessarily the case – the information stored on cloud infrastructure may be just as (un)safe as any other corporate data store.

Much of this risk comes from the misconception of the network position of cloud servers themselves. Although rented out for use by the company and used every day as part of fundamental business purposes, connections to cloud servers (if not facilitated by a VPN or other strong encrypted channels) cross the perimeter of the network and traverse the public internet. This means that data uploaded to and from the cloud is a prime target for man-in-the-middle attacks, carried out by opportunistic actors hoping to sniff usernames, passwords, and other sensitive details that they could then leverage for direct corporate data theft.

The reality is that while organizations can outsource their IT services, they cannot outsource their security function altogether. In fact, protecting the cloud comes with its own challenges, with most of the existing native security controls and third-party security solutions suffering from significant limitations.

Customer use case

A city government in the United States had outsourced the storage of SQL databases to a cloud storage provider. However, it had not interrogated the protocols that the server by default employed to upload and download information. Addresses, phone numbers, vehicle registration plate numbers: the city government was uploading it all to the external database via unencrypted connections. This highly sensitive data was intended for limited access by select employees within the city government, but the security oversight had made the data available to any attacker clued-up enough to park themselves on the perimeter of the network and collect the data-rich MySQL packets that came their way.

Sample of the plain text containing sensitive data.

Darktrace Cloud detected an unusual SQL connection to a rare external IP from a desktop device within the company. This communication was verified as being SQL-related via packet capture, which then revealed the sensitive public data.

The customer was unaware of this vulnerability, which remained under the radar of its entire security stack. An attacker could easily exploit it to gather material for spear phishing attacks or potentially even identity fraud.

Conclusion

In order to reduce risk and identify atypical or suspicious behavior, full visibility of all cloud services is critical, as hosting data on external servers can create dangerous blind spots and introduce subtle threats that circumvent traditional signature-based tools.

Already over 500 Darktrace customers use Darktrace Cloud to defend cloud environments and SaaS applications, including AWS, Microsoft Azure, Salesforce, and Google Cloud Platform. Darktrace provides businesses with fundamental visibility and real-time threat detection across their entire distributed infrastructures. Through the power of unsupervised machine learning, businesses are now able to confidently tackle the potential risks of data leakage and man-in-the-middle attacks that can affect cloud users.

About the authors

Justin Fier

Justin Fier is the Director for Cyber Intelligence & Analytics at Darktrace, based in Washington D.C. Justin is one of the US’s leading cyber intelligence experts, and his insights have been widely reported in leading media outlets, including Wall Street Journal, CNN, the Washington Post, and VICELAND. With over 10 years of experience in cyber defense, Justin has supported various elements in the US intelligence community, holding mission-critical security roles with Lockheed Martin, Northrop Grumman Mission Systems and Abraxas. Justin is also a highly-skilled technical specialist, and works with Darktrace’s strategic global customers on threat analysis, defensive cyber operations, protecting IoT, and machine learning.

Dave Palmer

Dave Palmer is the Director of Technology at Darktrace, overseeing the mathematics and engineering teams and project strategies. With over ten years of experience at the forefront of government intelligence operations, Palmer has worked across UK intelligence agencies GCHQ & MI5, where he delivered mission-critical infrastructure services, including the replacement and security of entire global networks, the development of operational internet capabilities and the management of critical disaster recovery incidents. He holds a first-class degree in Computer Science and Software Engineering from the University of Birmingham.

Andrew Tsonchev

Andrew advises Darktrace’s strategic Fortune 500 customers on advanced threat detection, machine learning and autonomous response. He has a technical background in threat analysis and research, and holds a first-class degree in physics from Oxford University and a first-class degree in philosophy from King’s College London. He was most recently featured on BBC World, BBC Morning and Al Jazeera to comment on the news regarding the GRU.

Max Heinemeyer

Max is a cyber security expert with over eight years’ experience in the field specializing in network monitoring and offensive security. At Darktrace, Max works with strategic customers to help them investigate and respond to threats as well as overseeing the cyber security analyst team in the Cambridge UK headquarters. Prior to his current role, Max led the Threat and Vulnerability Management department for Hewlett-Packard in Central Europe. He was a member of the German Chaos Computer Club, working as a white hat hacker in penetration testing and red teaming engagements. Max holds a MSc from the University of Duisburg-Essen and a BSc from the Cooperative State University Stuttgart in International Business Information Systems.