What is Data Exfiltration?

Learn more about data exfiltration and methods for preventing data loss in Data Protection 101, our series on the fundamentals of data security.

A Definition of Data Exfiltration

Data exfiltration is sometimes referred to as data extrusion, data exportation, or data theft. All of these terms are used to describe the unauthorized transfer of data from a computer or other device. According to TechTarget, data exfiltration can be conducted manually, by an individual with physical access to a computer, but it can also be an automated process conducted through malicious programming over a network.

Basically, data exfiltration is a form of a security breach that occurs when an individual’s or company’s data is copied, transferred, or retrieved from a computer or server without authorization, as Techopedia describes. While data exfiltration can be achieved using various techniques, it’s most commonly performed by cyber criminals over the Internet or a network. These attacks are typically targeted, with the primary intent being to gain access to a network or machine to locate and copy specific data.

Data exfiltration can be difficult to detect. As it involves the transfer or moving of data within and outside a company’s network, it often closely resembles of mimics typical network traffic, allowing substantial data loss incidents to fly under the radar until data exfiltration has already been achieved. And once your company’s most valuable data is in the hands of hackers, the damages can be immeasurable.

How Hackers Gain Access to Target Machines

Often, data exfiltration is achieved by hackers when systems rely on vendor-set, common, or easy-to-crack passwords. In fact, statistically, these systems are the ones that most often suffer from data exfiltration. Hackers gain access to target machines through remote applications or by installing a removable media device, in cases where they have physical access to the target machine.

Advanced Persistent Threats (APTs) are one form of cyber attack in which data exfiltration is often a primary goal. APTs consistently and aggressively target specific companies or organizations with the goal of accessing or stealing restricted data. The goal of an APT is to gain access to a network, but remain undetected as it stealthily seeks out the most valuable or target data, such as trade secrets, intellectual property, financial information, or sensitive customer data.

APTs may rely on social engineering techniques or phishing emails with contextually relevant content to persuade a company’s users to inadvertently open messages containing malicious scripts, which can then later be used to install additional malware on the company’s network. Following this exploit is a data discovery stage, during which hackers rely on data collection and monitoring tools to identify the target information. Once the desired data and assets are discovered, data exfiltration techniques are used to transfer the data.

When cyber criminals successfully carry out data exfiltration, they may use the newly obtained data to damage your company’s reputation, for financial gain, or sabotage.

How to Prevent Data Exfiltration

Because data exfiltration often relies on social engineering techniques to gain access to protected company networks, preventing your users from downloading unknown or suspicious applications is a proactive preventative measure that companies should take. But in actuality, it’s quite difficult to adequately block the download of these malicious applications without restricting access to applications your users need. In order to effectively compromise an endpoint, however, malware must be able to communicate externally with a command or control server to receive instructions or exfiltrate data. Detecting and blocking this unauthorized communication, then, becomes a viable method for preventing data exfiltration.

Endpoint Protection is a Critical Component of Data Exfiltration Prevention

Because data exfiltration focuses on retrieving, transferring, and copying data on endpoints, and endpoints have historically provided one of the easiest access points for hackers, enterprises must look to comprehensive endpoint detection solutions as a first-line defense against threats such as data exfiltration.

Data exfiltration seems like an easily preventable process, but the advanced attacks that occur regularly in the modern threat landscape require an all-encompassing approach to data protection that adequately monitors and protects every endpoint that exists within your company’s network.

Nate Lord


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