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In the United States, sensitive health information is protected under the Health Insurance Portability and Accountability Act (HIPAA). This act limits the disclosure of Protected Health Information (PHI) without the patient’s consent or knowledge. However, as medical care becomes web-integrated, many providers have chosen to use third-party web trackers for measurement and marketing purposes. This presents a security concern: third-party JavaScript requested by an online healthcare system can read the website’s contents, and ensuring PHI is not unintentionally or maliciously leaked becomes difficult. In this paper, we investigate health information breaches in online medical records, focusing on 459 online patient portals and 4 telehealth websites. We find 14% of patient portals include Google Analytics, which reveals (at a minimum) the fact that the user visited the health provider website, while 5 portals and 4 telehealth websites con- tained JavaScript-based services disclosing PHI, including medications and lab results, to third parties. The most significant PHI breaches were on behalf of Google and Facebook trackers. In the latter case, an estimated 4.5 million site visitors per month were potentially exposed to leaks of personal information (names, phone numbers) and medical information (test results, medications). We notified healthcare providers of the PHI breaches and found only 15.7% took action to correct leaks. Healthcare operators lacked the technical expertise to identify PHI breaches caused by third-party trackers. After notifying Epic, a healthcare portal vendor, of the PHI leaks, we received a prompt response and observed extensive mitigation across providers, suggesting vendor notification is an effective intervention against PHI disclosures.
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MineSweeper: An In-depth Look into Drive-by Cryptocurrency Mining and Its Defense
A wave of alternative coins that can be effectively mined without specialized hardware, and a surge in cryptocurrencies' market value has led to the development of cryptocurrency mining ( cryptomining ) services, such as Coinhive, which can be easily integrated into websites to monetize the computational power of their visitors. While legitimate website operators are exploring these services as an alternative to advertisements, they have also drawn the attention of cybercriminals: drive-by mining (also known as cryptojacking ) is a new web-based attack, in which an infected website secretly executes JavaScript code and/or a WebAssembly module in the user's browser to mine cryptocurrencies without her consent. In this paper, we perform a comprehensive analysis on Alexa's Top 1 Million websites to shed light on the prevalence and profitability of this attack. We study the websites affected by drive-by mining to understand the techniques being used to evade detection, and the latest web technologies being exploited to efficiently mine cryptocurrency. As a result of our study, which covers 28 Coinhive-like services that are widely being used by drive-by mining websites, we identified 20 active cryptomining campaigns. Motivated by our findings, we investigate possible countermeasures against this type of attack. We discuss how current blacklisting approaches and heuristics based on CPU usage are insufficient, and present MineSweeper, a novel detection technique that is based on the intrinsic characteristics of cryptomining code, and, thus, is resilient to obfuscation. Our approach could be integrated into browsers to warn users about silent cryptomining when visiting websites that do not ask for their consent.
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- Award ID(s):
- 1704253
- PAR ID:
- 10097424
- Date Published:
- Journal Name:
- 2018 ACM SIGSAC Conference on Computer and Communications Security
- Page Range / eLocation ID:
- 1714 to 1730
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3243734.3243858
