Stolen Data: A Lucrative Business on the Dark Web

Exposed personal information is a goldmine for cybercriminals. Learn how stolen data is exploited, its risks, and how to protect yourself with strong passwords, MFA, and credit freezing.

As a threat researcher who monitors cybercriminal activity across the web, I’ve witnessed firsthand how bad actors rapidly trade, sell, and exploit stolen data. With major breaches regularly compromising vast amounts of personal information, it’s clear that the value of this data isn’t just in its collection — it’s in how cybercriminals use it. From identity theft and account takeovers to elaborate social engineering scams, stolen data circulating on the dark web has serious implications for individuals and businesses. Today, we will cover the major risks associated with compromised personal information and how cybercriminals typically exploit it.

Active Exploitation of Stolen Data

1. Identity Theft and Financial Fraud: Personal data like Social Security numbers, birthdates, and credit card details are the cornerstone of identity theft. Using this information, cybercriminals can open fraudulent accounts, apply for loans, or file false tax returns. The growing number of breaches, such as the 2024 AT&T breach and the Equifax breach of 2017, have exposed millions of consumers to such risks. Once the data is in the hands of criminals, the damage can be immediate and widespread, with victims often unaware until their financial accounts have already been accessed or drained​.
   
2. Account Takeovers: Stolen credentials (usernames, passwords, etc.) are frequently used in account takeovers. Cybercriminals test these credentials across multiple platforms—banking sites, social media accounts, online stores—and they can steal money and sensitive information or even hijack the victim’s online presence once they gain access. The more extensive and personalized the information, the more convincing the attack becomes. That’s why breaches that expose full personal profiles, such as the Change Healthcare breach, make individuals more vulnerable to targeted attacks​.
   
3. Phishing and Social Engineering: Cybercriminals can use compromised data for more sophisticated phishing attacks. Armed with personal details like names, addresses, or even employer information, bad actors craft highly targeted emails or texts to trick victims into providing further sensitive data. These attacks can be particularly dangerous when attackers impersonate trusted institutions like banks or service providers, often leading to financial loss or further data exposure​.

Also Read: Cyber Threats 2025: Trends, Tactics, and Tech to Watch

The Dark Web Marketplace

1. Data Reselling: Stolen personal data is often sold in bulk on underground markets within the dark web. These transactions are lucrative for cybercriminals, who profit by selling “Fullz” (complete identity kits). Stolen credit card numbers, medical records, and login credentials from breaches like NPD and AT&T are readily available for purchase. What’s more concerning is that the demand for such data is constant, meaning it doesn’t just disappear—it gets reused, repackaged and resold for further exploitation.​

2. Syndicates and Exploitation Networks: Some cybercriminals specialize in aggregating large datasets and selling them to other criminals. These buyers might be individuals looking to perform more sophisticated attacks, like creating synthetic identities or infiltrating corporate systems. In essence, the dark web acts as a marketplace for this stolen data, which fuels several types of cybercrimes, from financial fraud to corporate espionage​

Long-Term Risks of Data Exploitation

The risks remain over time, even if your data isn’t immediately exploited. Cybercriminals may hold onto stolen data for months or years, waiting for the right opportunity. This dormant data can be used for future fraud, particularly when vulnerabilities in security practices emerge or new opportunities for exploitation arise. The reality is that once your data is out there, it’s difficult to completely remove it from circulation. The longer it circulates on the dark web, the more likely it is to be leveraged by other bad actors in increasingly sophisticated ways​.

Signs You May Be a Target

To protect yourself from these risks, you must monitor for signs that your data may be actively exploited. Here are a few things to look out for:

• Phishing Scams: If you receive unexpected emails, calls, or texts that seem urgent or ask for personal information, double-check their legitimacy before acting. Cybercriminals will often impersonate trusted institutions to gain further access to your data.
• Unusual Account Activity: Monitor your financial accounts, credit card statements, and credit reports for any signs of fraudulent activity. Alert your bank or credit provider if you notice anything unfamiliar.
• Fraudulent Tax Returns: Be aware of delays in your tax return or notices from the IRS indicating multiple returns filed under your name, which may indicate identity theft.
• Failed Login Attempts and Multi-Factor Authentication (MFA) Alerts: Watch for unfamiliar login attempts or MFA requests on your accounts. These could be a sign that someone is trying to gain access to your accounts using stolen credentials.

Also Read: Hacked: Is This the New Normal?

Be Proactive in Protecting Your Data

As a threat researcher, I’ve seen the consequences of compromised personal information firsthand. While stolen data circulating on the dark web is concerning, there are steps you can take to reduce the risk of being targeted. By using strong, unique passwords, enabling multi-factor authentication, and regularly monitoring your financial accounts, you can protect yourself from many risks associated with these types of breaches. Additionally, consider freezing your credit and setting up fraud alerts for extra protection. 

Freezing your credit means:

1. Stops Unauthorized Credit Applications:
   • A credit freeze blocks access to your credit report, so the application will be denied if someone tries to use your stolen personal information to open a new credit account.
2. Does Not Affect Existing Accounts:
   • Freezing your credit does not impact your current accounts, credit card usage, or credit scores. You can continue using your existing credit as usual.
3. Free and Easily Accessible:
   • In the U.S., freezing and unfreezing your credit is free. You can initiate a freeze online, by phone, or via mail with the three major credit bureaus: Equifax, Experian, and TransUnion.
4. Flexible:
   • You can temporarily lift the freeze if you’re applying for credit, such as a loan or credit card. This can be done using a PIN or password provided when the freeze was set up.
5. Protects Against Fraud:
   • While a credit freeze doesn’t stop fraudsters from using your information for things like tax fraud or medical identity theft, it’s a strong deterrent for credit-related fraud.

How to Freeze Your Credit:

1. Contact each of the three major credit bureaus:
   • Equifax: www.equifax.com
   • Experian: www.experian.com
   • TransUnion: www.transunion.com
2. Provide proof of identity, such as your Social Security number, address, and a government-issued ID.
3. Set up a PIN or password to manage the freeze.

Staying proactive and informed about threats is the best defense against the exploitation of your personal information.

If you haven’t yet taken the necessary precautions, it’s time to act now. Cybercriminals are constantly looking for new opportunities to exploit the data they’ve stolen, and the consequences can be long-lasting.