What Is Data Exfiltration?

Data exfiltration refers to the unauthorized transfer or theft of data from a server, computer, or database, often involving malicious actors or insider threats. The data exfiltration meaning in cybersecurity highlights it as a serious threat where sensitive information is illicitly moved outside an organization’s secure environment. Terms like data exfiltration, data exportation, and data extrusion are often used interchangeably, but each has specific nuances in the context of cybersecurity. It is important to distinguish data exfiltration from data leakage and data breach—while all are forms of data compromise, data leakage typically refers to accidental exposure, and a data breach is a broader incident involving unauthorized access to data.

Download the Cyber Security Report

Why Data Exfiltration Poses a Critical Risk to Modern Organizations

Valuable data targeted in these attacks often includes sensitive information, intellectual property, and sensitive corporate data, such as proprietary business documents, personal details, and confidential files. Such data is highly sought after by cybercriminals and malicious insiders for purposes like extortion, espionage, or financial gain. The risks of data exfiltration for organizations include financial loss, reputational damage, and regulatory penalties.

To address these data exfiltration risks, security teams must implement robust security controls and security measures, such as endpoint protection, behavioral analysis, and unified security management. Detecting data exfiltration and blocking data transfers—whether at rest, in motion, or in use—are essential components of a comprehensive defense strategy. Preventing data exfiltration requires cybersecurity teams to mitigate common threats, create data protection policies, and use effective defensive mechanisms.

How Does Data Exfiltration Occur?

Data exfiltration happens when a malicious actor manages to gain access to private information and successfully transfers it out of your networks to third-party storage or an external location. Data exfiltration can be conducted manually by insiders or automated using malicious software such as malware. Attackers often begin with data collection, gathering sensitive information from devices and networks before exfiltrating it. As with all forms of cybersecurity threats, the exact mechanism of attack can vary, making a holistic approach to protecting your data the most effective.

To prevent data exfiltration, your business should understand the main methods used to steal data and begin to defend against them:

Weak or Stolen Credentials: If employees use weak passwords or have their account access hijacked, malicious parties have a direct pathway to access your company data. Be sure to educate employees on strong password practices and enable multi-factor authentication (MFA).) to protect user accounts.
Backdoor Application Vulnerabilities: When your business continues to use outdated software or misconfigured applications, you’re leaving the door open to potential exploits that hackers can use to break into your system. Attackers may use remote code execution to compromise systems and initiate data exfiltration. Regularly patch your systems and always install the most recent version of applications to ensure their security is up-to-date.
Malware: Malware, a type of malicious software, can be injected into computers or mobile devices connected to the corporate network to exfiltrate data and steal sensitive data. It aims to infect user devices, even potentially remaining hidden on a computer for long periods of time, and can begin to silently exfiltrate important data. Businesses should use anti-malware tools, invest in 360-degree cybersecurity protection, and improve visibility into their connected endpoint devices to identify and neutralize malware as quickly as possible.
Social Engineering: Social engineering attacks occur when malicious parties trick employees into giving up their account details or clicking on a malicious link. Phishing attacks are a common method used to gain unauthorized access and facilitate unauthorized data transfer. Security awareness training can significantly reduce the likelihood of a successful social engineering attack, as can additional account verification steps like MFA.
Excessive Permissions: Complicated permissions systems may have gaps or overlaps that give data access to individuals who shouldn’t have it. Permission structures need to be clear, direct, and all-encompassing. Create detailed permissions structures that do not overlap, and then begin to apply the principle of least privilege to ensure only the right people have access to your data.
Insider Threats: An insider threat is when an employee actively seeks to exfiltrate important data out of your company. Insiders may use external devices such as USB drives to conduct unauthorized copying and transfer data to an external location. Enhancing visibility into your data systems will help flag when an employee is interacting with your data in unexpected or malicious ways.
Cloud Storage and Cloud Services: Employees or attackers may misuse or intentionally transfer sensitive data to personal or third-party cloud storage or cloud services, facilitating unauthorized data transfer and data exfiltration attacks. Monitoring and controlling these destinations is essential to prevent data leaks.
Physical Attacks: Physical attacks are the theft of any devices that contain private company information. If a laptop is stolen or a USB is lost, you may have a data exfiltration event on your hands. Physical access control systems or using virtualized access for physical devices can help minimize these risks.
Data Misuse and Human Error: Human error causes 95% of security breaches, demonstrating just how important it is to teach employees about how to protect themselves. Simply uploading data to the wrong place or sending confidential information to the wrong email address could be all it takes to inadvertently cause an exfiltration event.

Attackers often use common data exfiltration techniques such as anonymizing connections to external servers and tunneling over HTTP or HTTPS. They may blend exfiltration activities with normal network traffic to avoid detection, making it difficult for traditional security solutions to identify unauthorized data transfer. Monitoring network traffic for anomalies and using advanced security tools are critical for detecting suspicious activity. Security teams rely on these tools to block data exfiltration attempts and protect sensitive information.

While not an exhaustive list, the sheer scope of potential points of access for an exfiltration event demonstrates the importance of building robust and expansive control systems in your business.

The Various Types of Stolen Data

Absolutely any form of company data could be stolen, spanning from highly sensitive financial records to archived meeting notes. Attackers often target valuable data such as sensitive information, sensitive corporate data, and intellectual property—including trade secrets, research and development, and other proprietary information essential to an organization’s profitability. In most cases, malicious actors will actively seek out such data that they can sell to the black market or use to conduct further cyberattacks. For example, customer credit card details might sell well online, while a list of employee usernames and passwords could help attackers to exfiltrate more data down the line.

Here is a broad overview of the common types of exfiltrated data:

Personally Identifiable Information (PII): PII is a common target for cyberattackers, as it can fetch a high value when sold.
Financial Data: Just like PII, financial information (company or customer) is a lucrative form of data that attackers will target.
Account Information: Usernames, emails, passwords, and access information all allow hackers to push further into a company’s system and steal more data.
Industry-specific Data: Certain industries, like the medical field, could see industry-specific data being exfiltrated.
Intellectual Property and Sensitive Corporate Data: Data collection by attackers often focuses on intellectual property, trade secrets, research and development, and other sensitive corporate data, the exfiltration of which can significantly impact an organization’s profitability and competitive advantage.

Of course, while these are the intended forms of data that attackers go after, exfiltration could also include less relevant or useful documents, like outdated project files or internal emails with no sensitive data.

Consequences of Data Theft

The consequences of data exfiltration depend directly on the type of stolen data and what the attacking group is going to use it for. Data exfiltration attacks are becoming more common and are a major factor in modern ransomware incidents. Beyond any associated costs of losing that data, companies also have to contend with social backlash and regulatory fines for breaking compliance.

The main consequences of data theft include:

Financial Loss: The most obvious and often most extensive damage caused by data exfiltration is financial loss. Businesses may have to pay legal fees, regulatory fines, and incident response costs. The average ransomware payment has significantly increased, reflecting the growing financial impact of data exfiltration incidents.
Compliance Penalties: Depending on the exact type of data that hackers exfiltrate, businesses may have to pay non-compliance penalties for failing to protect information that falls under regulatory protection. For example, if a medical company lost patient records, then they would be in non-compliance with HIPAA, incurring significant fines.
Reputational Damages: It’s extremely difficult to keep any data breach event completely private, with newspapers and industry publications reporting on exfiltration. If customers realize their data is included in one of these events, they could lose trust in your business and decide to look for an alternative.
Operational Disruptions: Especially if the total volume of exfiltrated data was significant, businesses may have to pause operations while they recover the data or rebuild it. During any downtime, businesses incur even more extensive financial losses as they’re unable to continue work and service their clients.
Personal Consequences: Stolen data is often sold on the dark web, increasing the risk of identity theft, credit card or bank fraud, and blackmail or extortion for affected individuals.

Data exfiltration incidents are increasing rapidly, with a significant percentage of organizations reporting such events. The repercussions of a data theft event scale fairly proportionally with the size of the breach. If only a few files were stolen, a business would likely be able to manage the damage with ease. On the other hand, a larger event would incur major penalties and lead to significant long-term damage.

Real-World Examples of Data Theft

Below are two real-world examples of data theft and exfiltration:

UK Ministry of Defence: A 2022 data exfiltration event for the MoD revealed PII of over 19,000 individuals who fled the Taliban regime to the United Kingdom. The event was ongoing for several years, with the actual individuals who were impacted only being notified in 2025.
Harrods Customer Data: In late 2025, Harrods was involved in a mass data exfiltration event that saw over 430,000 customer records stolen from the business. They could face extensive compliance penalties, as the stolen information related to personal names and contact details.

Best Practices for Preventing Data Exfiltration

Preventing data exfiltration isn’t a 1:1 task, as there is no singular cybersecurity protection that will effectively neutralize all forms of attack. As demonstrated earlier, there are numerous ways that a malicious actor could gain access to a company system, meaning there are multiple protections that businesses should use.

Here are some quick best practices and security policies to implement:

Verify user identities with zero-trust security to protect user accounts.
Gain visibility over user data with Data Loss Prevention (DLP) tools that prevent exfiltration.
Segment your network to divide up company systems and prevent lateral movement.
Patch all systems, applications, and third-party software regularly to ensure any known vulnerabilities are removed.
Monitor your systems and detect any suspicious behavior with network scanning tools.
Educate employees on what cybersecurity threats might look like to decrease the likelihood of a human-led exfiltration mistake.
Use identity management and MFA systems to make sure that the person using an account is who they claim to be.
Delete inactive company accounts and continually revise any active permissions to make sure no one has access to sensitive data beyond their permission level.

Protect Your Data with Check Point

Data exfiltration is the ultimate goal of many cyberthreats, with malicious actors aiming to liberate data from your organization and either use or sell it. Constructing a secure cybersecurity posture begins with effective DLP, with Check Point Quantum being the leading method of protecting your network and preventing unauthorized data movement.

Quantum Data Loss Prevention, integrated directly into Check Point’s Next Generation Firewalls, detects and blocks sensitive data from leaving your network in real time. In the case of an exfiltration event, an instant alert triggers, letting you protect your data before it leaves your organization.

Take your data security to the next level with Check Point’s GenAI Security Solutions, preventing confidential data from being exposed or exfiltrated through AI models and written prompts. Monitoring the flow of data in and out of GenAI applications with Check Point can precisely pinpoint where data exfiltration could occur, allowing you to mitigate leading threats before they happen.
Fortify your organization’s cyberdefenses and prevent exfiltration by getting started with a Check Point demo today.