Data leak prevention is a cybersecurity practice that involves implementing secure data practices to reduce accidental exposure. Effective data leak prevention plays a crucial role in a comprehensive data loss prevention strategy (DLP strategy).

Data leaks are an easy attack vector for cybercriminals. Exposed data, such as leaked credentials, allows unauthorized access to an organization's systems. This direct access enables hackers to carry out a range of cyber attacks with less effort, such as:

What is a Data Leak?

A data leak is an overlooked exposure of sensitive data, either electronically or physically. Data leaks could occur internally or via physical devices such as external hard drives or laptops. If a cybercriminal locates a data leak, they can use the information to arm themselves for a data breach attack.

When sensitive data is stolen from either a data breach or a ransomware attack and published on the dark web, these events are also classified as data leaks.

The Difference Between Data Leaks and Data Breaches

A data leak is the accidental exposure of sensitive information. These events are not initiated by an external impetus. They're caused by vulnerabilities in the security controls protecting confidential data. Data leaks can also be caused by cybercriminals publishing stolen data on their official dark web noticeboards, also known as ransomware blogs.

sensitive data moving through exposures in an IT boundary

A data breach, on the other hand, is the outcome of a planned cyberattack. These events are initiated by an external impetus. Before sensitive data can be detected and exfiltrated, cybercriminals must overcome a series of data security measures securing the cyber kill chain.

Sensitive data being accessed through vulnerabilities in an IT boundary

Learn how to prevent data breaches >

Data loss is another term commonly associated with data leaks. Data loss is the irreversible loss of sensitive data, either by accidental deletion or theft.

These events can be mitigated with Data Loss Prevention (DLP) strategies that prevent data transfer beyond specified boundaries. However, a DLP strategy alone will not prevent data leaks; its focus is too narrow.

Data leak prevention efforts need to consider all of the processes that have a direct and indirect impact on sensitive data protection. This effort even stretches as far back as the coding practices that develop a solution.

Sensitive data moving beyond an IT boundary and being lost forever

Learn more about the differences between data leaks, data breaches, and data loss >

Why is Data Leakage Prevention Important?

Leaked data is a treasured find for a cybercriminal. These events significantly reduce the effort of cybercrime by removing all of the laborious stages preceding data compromised in the cyber kill chain.

Red arrow pointing to the data breach phase (final phase) of the cyber attack priviledged pathway

Because they make life so much easier for cybercriminals, data leak finds are becoming a primary focus in the world of cybercrime. Meeting this performance metric is relatively easy, given the growing prevalence of data leaks.

A 2021 UpGuard study revealed that half of analyzed Fortune 500 companies were leaking data useful for cybercriminal reconnaissance in their public documents.

Also, in 2021, UpGuard researchers discovered that at least 47 organizations were unknowingly leaking data through a misconfiguration in Microsoft's PowerApp solutions - an oversight resulting in the exposure of tens of millions of private records.

Many organizations unknowingly leak sensitive data sets, potentially exposing trade secrets, Personal Identifiable Information (PII), and even credit card data.

The normalization of data breach prevention efforts will likely positively impact all other cybersecurity sectors. The degree of sensitive data exposure is proportional to the success of data breaches and phishing attacks. Both events could, therefore, be reduced if data leaks are remediated before cybercriminals discover them.

What Causes Data Leaks?

Data leaks occur when sensitive data is accidentally exposed publicly, either physically or digitally. Common causes of data leaks include:

Learn more about the common causes of data leaks >

Examples of Data Leaks

The holy grail of sensitive information exposure is Personally Identifiable Information (PII), including names, contact information, financial details, and other personal data. Other less potent forms of data leaks can be used for reconnaissance missions to uncover internal secrets.

There are four major categories of data leaks - customer information, company information, trade secrets, and analytics.

1. Customer Information

Some of the biggest data breaches included customer data leaks that involved Personal Identifiable information. Customer data is unique to each company. Customer confidential information could include any of the following:

  • Customer names
  • Addresses
  • Phone number
  • Email addresses
  • Usernames
  • Passwords
  • Social Security numbers
  • Payments histories
  • Product browsing habits
  • Credit Card numbers

2. Company Information

Leaked company information exposes sensitive internal activity. Such data leaks tend to be in the crosshairs of unscrupulous businesses pursuing the marketing plans of their competitors.

Company data leaks could include the following:

  • Internal communications
  • Performance metrics
  • Marketing strategies

3. Trade Secrets

This is the most dangerous form of data leak to a business. Intellectual property theft destroys a business's growth potential, running it to the ground.

Trade secret leakage could include the following types of data:

  • Upcoming product plans
  • Software coding
  • Proprietary technology information

4. Analytics

Large data sets feed analytics dashboards, and cybercriminals are drawn to any sizable pool of data. Analytics software is, therefore, an attack vector that needs to be monitored.

Analytics data leaks could include the following:

  • Customer behavior data
  • Psychographic data
  • Modeled data

Common Host of Data Leak Dumps

There has been enough data breach intelligence analyzed to paint a picture of common cybercriminal behavior. Thanks to this data, we can now deploy security controls along each stage of the cyberattack lifecycle.

Data breach post-mortem analysis has also unveiled common cybercriminal behavior beyond a successful breach. After exploiting leaked data, the next stop for cybercriminals is usually dark web forums, where they either put it up for sale or publish it freely.

Such forums need to be continuously monitored in a data leak detection strategy.

Data leaks could still offer helpful reconnaissance information while in the process of being sold. Dark web marketplace listings often include a sample of compromised data to prove the authenticity of the event.

By cross-referencing the sample information against your third-party vendor list and a database of known breaches, such as Have I Been Pwnd, the source of the leak could be identified.

The following popular dark web forums should be monitored for data leaks:

  • Nulled
  • Dread
  • Crackingking
  • Cryptbb
  • Raidforums
  • Freehacks
  • Hacktown
  • 4chan

Learn how to reduce data leak false positives >

Ransomware Blog Data Leaks

Another common cause of data leaks is data dumps from ransomware attacks. Hackers publish data stolen from ransomware attacks on dark websites known as ransomware blogs (or ransomware sites). Ransomware blogs are like noticeboards for specific ransomware groups, hosting official updates as well as data dumps.

A data leak prevention strategy must accommodate for these types of leaks by implementing security measures beyond the final phase of the ransomware attack lifecycle - after the data dump phase (phase 8).

Ransomware attack lifecycle

Learn how to reduce the impact of ransomware attacks >

A ransomware data leak security tool monitors popular ransomware blogs for critical data and internal confidential information (like employee credentials leaks). If ransomware leaks are left unaddressed, cybercriminals could use them to instantly gain access to a private network without the usual social engineering processes that preclude unauthorized access attempts.

Armed with internal credentials from a ransomware blog, cybercriminals could circumvent the perimeter penetration phases - the most difficult stages of a ransomware attack - leaving just the challenge of escalating permissions before a breach is achieved.

Ransomware attack lifecycle

The resulting compressed ransomware lifecycle, which makes data breaches easier and faster to accomplish, highlights the critical need for ransomware leak security measures in security policies.

Request a free demo of UpGuard's ransomware data leak solution >

Addressing the Source of Data Leaks

The most effective and sustainable cybersecurity initiatives are those that assume a proactive approach to protection.

Data leak monitoring efforts are reduced if the vulnerabilities facilitating data leaks are addressed.

This is most efficiently achieved with an attack surface monitoring solution. Such a solution will discover the security vulnerabilities inside your ecosystem and those throughout your third-party vendor network.

Monitoring the third-party attack surface is crucial since over half of data breach events result from compromised third-party vendors.

Since most breaches stem from compromised third parties, it's safe to assume that your vendors aren't addressing data leaks in their cybersecurity practices.

Because of this, the scope of a data leak detection strategy should also extend to the third-party landscape.

Since data leaks commonly preceded data breaches, this effort will reduce third-party breaches and supply chain attacks and, therefore, most data breach events.

8 Tips to Protect Your Business from Data Leaks in 2024

The following data security practices could prevent data leaks and minimize the chances of data breaches.

1. Evaluate the Risk of Third Parties

Unfortunately, your vendors may not take cybersecurity as seriously as you do. It's important to keep evaluating the security posture of all vendors to ensure they're not at risk of suffering data leaks through critical security vulnerabilities.

Vendor risk assessments are a common method of identifying third-party security risks and ensuring compliance with regulatory standards, such as HIPAA, PCI-DSS, or GDPR. Risk questionnaires could be compiled from templates based on existing frameworks or custom-built for bespoke security queries.

Learn about UpGuard's custom questionnaire builder >

It can be difficult for security teams to keep up with the risk management demands of a rapidly expanding third-party network. To prevent overlooked vendor risks while scaling cloud data and cloud storage, vendor risk management can be easily scaled as a managed service.

2. Monitor all Network Access

The more corporate network traffic being monitored, the higher the chances of identifying suspicious activity. Cyber attacks are usually preceded by reconnaissance campaigns - cybercriminals need to identify the specific defenses that need circumventing during an attack.

Data leak prevention solutions empower organizations to identify and strengthen security vulnerabilities to prevent the possibility of reconnaissance campaigns.

Information security policies may need to be revised to enforce privileged access to highly sensitive data.

3. Identify All Sensitive Data

Data Loss Prevention (DLP) should be front of mind for organizations looking to enhance their data leak prevention strategies. Before DLP policies can be initiated, businesses need to identify all of the sensitive data that needs to be secured. This data then needs to be correctly classified in line with strict security policies.

Data classification categories could include Protective Health Information, financial data, and other sensitive data forms.

With correct sensitive data discovery and classification, a business can tailor the most efficient data leak prevention defenses for each data category.

4. Secure All Endpoints

An endpoint is any remote access point that communicates with a business network via end-users or autonomously. This includes Internet of Things (IoT) devices, desktop computers, and mobile devices.

With most organizations now adopting some form of a remote working model, endpoints have become dispersed (sometimes even internationally), making them harder to secure. Organizations must extend their coverage to cloud-based endpoint security.

Employees with iPhone access to their organizations' networks should ensure they use the Security Recommendations feature, which identifies if any of their saved credentials have been compromised in a data leak.

Firewalls and VPNs offer a base layer of endpoint security, but they're not enough on their own. Staff are often tricked into introducing malware into an ecosystem to bypass these security defenses.

Organizations need to train their staff to recognize the trickery of cyberattackers, particularly email phishing and social engineering attacks. Education is a very powerful data leakage prevention solution. Securing endpoints is a fundamental component of Data Loss Prevention (DLP).

5. Implement Data Loss Prevention (DLP) Software

Data loss prevention (DLP) is an overarching data protection strategy that should include data leak prevention as a core component. An effective DLP system combines processes and technology to ensure sensitive data is not lost, misused, or exposed to unauthorized users.

Below are the six components of a DLP program  requiring DLP solutions:

1. Data identification: Many organizations leverage automation techniques, such as machine learning and artificial intelligence (AI), to streamline the data identification process.

2. Securing data in motion: Deploy DLP software at the network edge to detect sensitive data transfers violating data loss prevention policies.

3. Securing endpoints: Endpoint DLP agents can monitor user behavior in real-time and control data transfers between specified parties, e.g., through instant messaging apps.

4. Securing data at rest: DLP products can enforce access control, regulatory compliance requirements, encryption algorithms, and data storage policies to protect archived data.

5. Secure data in use: Comprehensive DLP tools can monitor and flag unauthorized user behavior, e.g., unauthorized privilege escalation on an app.

6. Data leak detection: If data leak prevention strategies fall through, fast remediation is crucial to avoiding a data breach. Effective data leak detection tools can scan the open and deep web for data exposures, including S3 buckets and GitHub repositories, enabling faster removal of potential breach vectors.

6. Encrypt All Data

Cybercriminals may find it difficult to exploit data leaks if the data is encrypted. There are two main categories of data encryption - Symmetric-Key Encryption and Public-Key Encryption.

While encrypted data may stump amateur hackers, capable cyber attackers could decrypt the data without a decryption key. For this reason, data encryption shouldn't be the sole data leak prevention tactic but should be used alongside all the methods in this list.

Learn how tech companies can detect data leaks >

7. Evaluate All Permissions

Your confidential data could currently be accessed by users that don't require it. As an initial response, all permissions should be evaluated to ensure access isn't being granted to authorized parties.

Once this has been verified, all critical data should be categorized into different levels of sensitivity to control access to different pools of data. Only trustworthy staff with essential requirements should have access to highly sensitive data.

This privileged access assignment process may also identify malicious insiders facilitating sensitive data exfiltration.

Learn more about Privileged Access Managemet >

8. Monitor the Security Posture of All Vendors

Sending risk assessments will prompt vendors to strengthen their cybersecurity efforts, but without a monitoring solution, remediation efforts cannot be confirmed.

Security scoring is a highly efficient way of evaluating a vendor's susceptibility to data breaches. These monitoring solutions display all vendors in the third-party network alongside their security rating, giving organizations instant transparency into the health status of their entire vendor network.

The UpGuard platform assigns all vendors a security score based on an analysis of 70+ critical vectors.
Security ratings by UpGuard
Security ratings by UpGuard

Learn more about UpGuard's security rating feature >

Watch the video below for an overview of UpGuard's data leak detection features.

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