What is Data Exfiltration?

Data exfiltration is the act of unlawfully removing data from a protected setting, typically with harmful intentions. It involves the improper extraction of data, resulting in a data breach and the potential for the data to be obtained by unauthorized individuals. It can be described as a sophisticated term for theft and can be carried out by external parties, as well as insiders such as employees and contractors, making it challenging to identify until it has already occurred.

The process of data exfiltration involves sending privileged or sensitive information from a computer to an external destination without proper authorization. It can happen either manually, with physical access to a device, or automatically through malicious programming via networks. It’s an especially grave threat to organizations with a plethora of customer data, since data is the lifeblood of your organization, and in being the basis of innovation, provides you with a competitive advantage.

If a cyber-attack aimed at stealing data or a malicious insider is able to achieve its goal, the consequences of data exfiltration could be disastrous. Apart from the expenses and disruptions involved in addressing the breach, an exfiltration attack may result in punitive measures from regulatory bodies, such as fines under GDPR or CCPA. There is also the possibility of facing legal consequences and reputational harm, particularly if sensitive email communications are made public.

In order to maintain the security of important information, it is crucial for data protection policies and practices to account for the possibility of data being stolen. By actively protecting your systems, you can safeguard all sensitive data from being accessed by malicious individuals. This piece tackles this concern and explores common methods used to extract data, as well as potential strategies that organizations can implement to thwart such attempts.

How does data exfiltration occur?

The objective of a cyber attacker is often to extract data. According to the MITRE ATT&CK framework, exfiltration is the second-to-last step in their multi-phase approach to a cyber assault. It takes place after gaining access to the target’s network, locating valuable data, avoiding detection, and maneuvering to the location where the data is kept. In the ATT&CK framework, only Command and Control (C2) follows exfiltration. However, since data is typically the end goal, the attacker may not even bother with command and control.

Cyber defenders are facing a situation that could be either positive or negative. On the bright side, they have numerous opportunities to prevent an attacker from stealing data. However, on the downside, the attackers also have many opportunities to access the data.

A data exfiltration attack from an outside source begins when a hacker breaches a company’s system to obtain sensitive data, including user passwords, or through the use of APIs, which offer the easiest route for accessing data. Hackers typically insert harmful software into devices used by end-users, such as computers or phones connected to the company’s network.

After infiltrating an organization’s systems and devices, malware can rapidly proliferate while targeting valuable corporate data for theft. It is adept at evading the organization’s security measures until it successfully fulfills its objectives, whether by swiftly gathering a large amount of data or slowly accumulating small pieces of information without being detected.

Corrupt insiders also pose a dangerous threat to organizations. They can quickly steal confidential data and move it out of the organization via email or cloud storage for their financial gain. Unintentional mistakes made by personnel can also cause security breaches. For example, an internal user could unknowingly leak data from the network by forwarding it to their personal email or saving it on unprotected cloud-based services and software platforms. While these actions may seem harmless, they inadvertently create vulnerabilities that are outside of the purview of the organization’s security team.

One of the primary obstacles in preventing data exfiltration attacks is distinguishing between legitimate and malicious data exports. It can be difficult to determine if a user downloading a file is engaging in cyber attack activity or simply performing their job duties. Similarly, it can be challenging to identify whether encrypted data leaving an organization’s network is part of a normal business transaction or a malicious attack.

During the infamous Sony Pictures hack, a vast amount of information was extracted from the company’s network in an encrypted state over several months without detection, exposing a major flaw in their anti-exfiltration measures. This is not an isolated issue, as it affects every organization in some capacity.

Types of data exfiltration

Data can be stolen through different methods and approaches, such as online or within a company’s internal system. Cybercriminals have created numerous advanced methods to illegally obtain data from companies, including masking connections, using DNS tunneling, utilizing direct IP addresses, carrying out fileless attacks, and implementing remote code execution. These strategies enable criminals to avoid detection while trying to obtain confidential data.

Cybercriminals employ a variety of data exfiltration tactics and malicious attack strategies, including:

• Phishing attacks: Cybercriminals use phishing emails to trick individuals into giving up their login credentials, which the attacker can use to access sensitive data.
• Outbound emails: Attackers can use outbound emails to send sensitive data to external email addresses outside the organization.
• Downloads to insecure devices: Attackers can download sensitive data to insecure devices, such as personal laptops or USB drives, and then use that data for malicious purposes.
• Uploads to external platforms: Attackers can also upload data to external platforms, such as cloud storage services, to exfiltrate it.
• APIs: As confirmed above, APIs are the path of least resistance to data. Attackers can exfiltrate data by abusing APIs.

It is important to note that these are just a few of the many types of data exfiltration techniques that attackers use. As attackers become more sophisticated, they constantly develop new strategies to steal sensitive data.

How to prevent data exfiltration

Companies should be proactive in avoiding any attempts to steal data. To effectively safeguard an organization’s confidential data from cyber criminals, consider implementing a security system that incorporates features like:

• Restricting access to unauthorized communication channels: To prevent data exfiltration, organizations should take steps to block unauthorized external communications, such as those from compromised applications.
• Safeguarding against credential theft and phishing attacks: To combat the growing number of phishing attacks, organizations should adopt tools that prevent users from entering their credentials on fraudulent websites. These preventative measures can also thwart keystroke logging, a technique used by criminals to spy and record a user’s keyboard inputs, including user IDs and passwords.
• Empowering users: To effectively detect and prevent data exfiltration, organizations must provide comprehensive training to their employees on the risks and tactics of cyberattacks. This training should equip employees with the knowledge to identify warning signs and take appropriate actions, such as avoiding suspicious email attachments and refraining from clicking on unfamiliar links. These measures are essential and fundamental steps towards enhancing overall digital security.

All that said, preventative data exfiltration measures mustn’t interfere with users’ activity. To ensure a good user experience, organizations should adopt tools that can accurately detect legitimate communication and application use, even in unfamiliar applications.

Conclusion

Data exfiltration is a growing and increasingly sophisticated security threat. Organizations must implement the proper precautions to guarantee that confidential information stays safe. Limiting access to unapproved sources is vital, as well as providing employees with the necessary knowledge to protect themselves from potential cyber risks. With an informed understanding of data exfiltration tactics and a robust strategy for prevention, organizations can confidently safeguard data and networks.