What happens to your stolen data after a security breach?

Companies and nonprofits work hard to be good stewards of the sensitive data they collect from employees, customers, vendors, and other stakeholders. When a security break compromises that data, companies can be left feeling exposed and vulnerable, and the consequences can be devastating. Thinking about sensitive data as a commodity to be stolen, bought, and sold by threat actors makes that feeling of exposure so much worse.

Unfortunately, this scenario has become increasingly common, and the financial ramifications can be significant. The global average total cost of a data breach in 2025 reached nearly $5 million, a 12% increase from the year prior¹.

So, what happens to an organization’s data once it has been stolen? Understanding what attackers may do with it and, more importantly, what you can do to reduce risk are crucial in helping to protect employees, customers, business partners, and the organization itself.

What is the dark web?

Most online content can’t be found through traditional search engines. Much of that unindexed content sits behind paywalls, private databases, or account logins. A smaller percentage, though, is intentionally hidden and may require specialized software or browsers to access it.

The deep web contains more than 90% of all online content². This content is not indexed by conventional search engines and is often restricted to authorized users. Examples include electronic health records, emails, social media messages, and information behind paywalls or account logins.

The dark web goes a layer further. It’s a smaller portion of the deep web that is intentionally concealed and generally accessed only through specialized software designed to provide anonymity. Although the dark web could support legitimate privacy needs, it also hosts marketplaces and forums used for criminal activity.

What is available on the dark web?

The dark web can provide users with a high degree of anonymity and access to a wide range of content and services, sometimes for the purpose of circumventing or disregarding legality. While not all content on the dark web is illegal, it can host thriving marketplaces for stolen data, credentials, network access and personally identifiable information (PII).

• Stolen personal information: Dark web marketplaces may offer sensitive data such as Social Security Numbers (SSN), driver’s license information and credit card data.
• Fraud networks: Fraudsters may use dark web forums to collaborate, exchange stolen information and coordinate fraudulent activity.
• Insider threats & data leaks: Employees, contractors, or cybercriminals with unauthorized access to sensitive information may attempt to sell it or disclose it on the dark web.
• Cyber threats and ransomware: Cybercriminals leverage dark web marketplaces to buy and sell hacking tools, malware, ransomware, and unauthorized access to compromised networks.

Accessing the dark web to purchase stolen credentials or network access allows cybercriminals to bypass some of the work required to identify and compromise a target themselves.

What is stolen data worth on the dark web?

Cybercriminals rely on a steady supply of stolen credentials and personal information to fuel fraud and cyberattacks. Data exposed in breaches is often shared, sold or reused across multiple criminal groups, allowing attackers to launch account takeover, ransomware, and business email compromise schemes at scale.

Even highly sensitive information is often inexpensive for criminals to acquire and demand is high. The 2026 Data Breach Investigations Report (DBIR) found that stolen credentials were used in 36% of reported breaches³. This widespread availability of stolen information reinforces the importance of strong passwords, multi-factor authentication, employee education, and proactive account monitoring.

How should an organization respond if its data appears on the dark web?

Determining whether your organization’s information is on the dark web one component of an effective cybersecurity program. Consider using dark web or identity monitoring tools to help find leaked or stolen information that is being shared and sold among cybercriminals operating on the dark web.

1. Use a reputable breach-monitoring service or an organization-approved security tool to determine whether usernames, passwords or other account information may have appeared in a known breach. Checking these sites is often the first step in discovering if your credentials have been compromised.
2. If account information has been exposed, such as credentials for an email or social media account, identify the username and password associated with it. Pay close attention to whether the compromised password was one you frequently reuse or modify slightly, such as changing the numbers at the end. Immediately change the compromised password and any other password that is identical or substantially similar.
3. Determine whether the compromised credentials are connected to other accounts, systems, or networks. Threat actors can collect these credentials and use them in attempts to access additional services.

Discovering exposed information should also trigger your organization’s documented incident-response and escalation procedures. Relevant security, legal, compliance, risk, communications, and executive stakeholders could need to assess the exposure and determine whether additional action is required.

Other protective measures include:

• Using security scanning tools to detect and manage vulnerabilities and help reduce the risk of network and equipment compromise.
• Requiring multifactor authentication (MFA) for sensitive systems and enforcing strong password and access-management practices across the organization.
• Providing regular cybersecurity education to help employees recognize common tactics, including business email compromise (BEC) and social engineering.
• Limiting access to sensitive data based on business need and regularly reviewing user privileges, particularly when employees or contractors change roles or leave the organization.
• Maintaining and testing an incident-response plan that assigns responsibilities for investigating, containing, and communicating a suspected breach.

Remaining vigilant against cyber threats and raising awareness of the risks with your company can help prevent costly data breaches.

Dark web monitoring cannot recover stolen data or eliminate the risk that it will be misused. However, timely detection, clear escalation procedures, and layered security controls can help an organization respond more effectively and reduce the likelihood that exposed information will lead to additional harm.