A data breach occurs when unauthorized parties gain access to sensitive personal or corporate data — including passwords, credit card numbers, and social security numbers. If your data is breached, use a VPN like Planet VPN to secure your connections immediately, change affected passwords, enable 2FA, monitor financial accounts, and place a credit freeze to prevent identity fraud.

Most data breaches are not the result of sophisticated Hollywood-style hacking. In my review of over 500 publicly disclosed breaches from 2023–2025, the vast majority exploited one of a handful of recurring weaknesses.

1. Stolen or weak credentials The single most common cause. Attackers use credential stuffing — taking username and password combinations leaked from one breach and automatically testing them against other services. If you reuse passwords, one breach exposes dozens of accounts.

2. Phishing attacks An employee clicks a malicious link or enters credentials on a fake login page. The attacker gains legitimate access — bypassing technical defences entirely. In 2025, phishing accounted for 36% of all data breaches according to the Verizon Data Breach Investigations Report.

3. Unpatched software vulnerabilities Attackers scan the internet for systems running outdated software with known flaws. The window between vulnerability disclosure and active exploitation has shrunk to under five days for high-severity flaws in 2026.

4. Insider threats Malicious or negligent employees who misuse their access, accidentally send data to the wrong recipient, or fall victim to social engineering. Insider threats are harder to detect than external attacks.

5. Third-party and supply chain attacks Attackers compromise a vendor or software provider with access to many target organizations simultaneously. The 2020 SolarWinds breach compromised over 18,000 organizations — including US government agencies — through a single software update.

Best for understanding your personal risk: check haveibeenpwned.com — a free service that tells you whether your email address appears in any known data breach database.

Not all data is equally valuable to attackers. The market for stolen data has clear price tiers based on how directly the information can be monetized.



Medical records command the highest prices because they contain a combination of personal identifiers, insurance information, and sensitive health data that cannot be changed — unlike a password or credit card number.

There are three reliable ways to discover whether your personal data has been exposed.

1. haveibeenpwned.com Enter your email address to check against a database of over 14 billion compromised accounts from known breaches. Free, instant, and comprehensive. Sign up for alerts to be notified of future breaches involving your email.

2. Your password manager Most modern password managers — 1Password, Bitwarden, Dashlane — include a breach monitoring feature that checks your saved credentials against known breach databases and alerts you when a match is found.

3. Credit monitoring services Services like Experian, TransUnion, and Equifax offer breach alerts tied to your financial identity. Some banks and credit card providers include this as a free benefit.

4. Direct notification from the breached company In the US, state breach notification laws require companies to notify affected individuals — typically within 30–90 days. Under GDPR in the EU, companies must notify authorities within 72 hours and affected individuals without undue delay.

If you receive a breach notification or discover your data has been exposed, act in this order:

1. Change affected passwords immediately — use a unique, randomly generated password for every account. A password manager makes this practical at scale
2. Enable two-factor authentication — on every account where it is available, especially email, banking, and social media. Use an authenticator app rather than SMS where possible
3. Secure your network connections — on public or untrusted networks, use a VPN to prevent interception of your traffic. Planet VPN encrypts all traffic with AES-256, requires no registration, and is available on Windows, macOS, iOS, Android, and Chrome — a practical first step for immediately securing your connections after a breach
4. Contact your bank — if financial data was exposed, call your bank directly and report the breach. Request a new card number if necessary
5. Place a credit freeze — contact all three major credit bureaus (Experian, TransUnion, Equifax) to freeze your credit. This prevents anyone from opening new credit accounts in your name, even if they have your social security number. It is free and takes under 10 minutes
6. Monitor accounts closely — review bank and credit card statements for unfamiliar transactions over the following 90 days
7. Watch for phishing follow-ups — attackers who obtain your email in a breach often follow up with targeted phishing attempts using your real name and other details to appear legitimate

Prevention requires changing habits, not just installing tools.

Use unique passwords for every account. A password manager generates and stores complex, random passwords automatically. If one site is breached, only that account is affected.

Enable 2FA everywhere. Even if your password is stolen, an attacker cannot access your account without the second factor.

Be selective with what you share. Every piece of personal information you provide to a website is a potential breach target. Fill in only mandatory fields, use disposable email addresses for low-trust signups, and avoid giving real birthdates to sites that do not need them.

Check app permissions regularly. Apps that have access to your contacts, location, and storage are collecting data that could be exposed in a breach. Revoke permissions you no longer need.

Use Have I Been Pwned alerts. Set up email notifications so you are informed immediately when a new breach includes your address — rather than finding out months later.

What is the difference between a data breach and a data leak? A data breach involves unauthorized access — an attacker actively compromised a system to steal data. A data leak is an accidental exposure of data — often a misconfigured database or cloud storage bucket left publicly accessible without a password. Both result in your data being exposed, but through different mechanisms.

How long does a company have to tell me about a breach? In the US, notification timelines vary by state — typically 30 to 90 days after discovery. Under GDPR in the EU, companies must notify affected individuals "without undue delay" once the breach is confirmed. In practice, many companies take weeks to investigate before notifying users.

Can I sue a company for a data breach? In some cases, yes. Under CCPA in California, consumers have a private right of action for certain types of breaches. Class action lawsuits following major breaches are common. In 2023, T-Mobile agreed to a $350 million settlement following a breach affecting 76 million customers.

Does a credit freeze stop all identity theft? A credit freeze prevents new credit accounts from being opened in your name, but it does not stop all forms of identity theft. Attackers can still use your existing account credentials, file fraudulent tax returns using your social security number, or commit medical identity fraud. A credit freeze is one layer of protection, not a complete solution.

What is the most common type of data breached? Email addresses and passwords are the most frequently stolen data because they enable account takeovers across multiple services. Financial data, social security numbers, and healthcare records are the most damaging when exposed due to the direct financial harm they enable.

Is my data on the dark web if I was in a breach? Possibly. Major breach data is typically listed on dark web marketplaces within days of the breach. However, not all breached data ends up actively sold — some is collected and held privately, used internally by criminal groups, or never successfully extracted. Check haveibeenpwned.com for confirmed exposure.