What to Do If Your Data Appears in a Leak

2026-02-05·6 min read

You just checked your email in a breach scanner and the result isn't good: your data appears in one or several leaks. Now what? Don't panic. This guide explains exactly what to do, step by step.

Step 1: Don't panic, but act fast

That your data appears in a breach doesn't automatically mean someone has used it. But it does mean that it is available for anyone who wants to use it. The sooner you act, the lower the risk.

Step 2: Identify what data was leaked

Not all breaches expose the same data. Review the scanner result to know exactly what was leaked:

| Leaked data | Risk level | Immediate action | |---|---|---| | Email only | Low | Be alert for phishing | | Email + password | High | Change the password now | | Email + password + phone | Very high | Change password + enable 2FA | | Financial data | Critical | Contact your bank | | ID document | Critical | Report to the authorities |

Step 3: Change compromised passwords

Start with the service that suffered the breach, but don't stop there. If you used the same password on other sites (something more than 60% of people do), change them all:

Change the password of the leaked service
Change the same password on any other service where you use it
This time, use a unique password for each one
Use a password manager so you don't have to memorize them

Step 4: Enable two-factor authentication (2FA)

Prioritize these services:

Your main email — It's the key to resetting passwords for everything else
Financial services — Online banking, PayPal, investment services
Social networks — To prevent identity theft
Work services — If your work email is affected

Step 5: Review suspicious activity

Log into the accounts that could be compromised and look for:

Logins from unknown locations
Devices you don't recognize connected to your account
Changes in settings that you didn't make
Messages sent that you didn't write
Purchases or transactions you don't recognize

If you detect something suspicious, act:

Close all active sessions
Change the password again
Contact the service's support

Step 6: Be alert for phishing

After a leak, it's common to receive especially targeted phishing emails. Attackers use your leaked data to make emails more credible:

"We have detected suspicious activity on your account" (using your real name)
"Your package could not be delivered to [your address]"
"Update your payment method" (mentioning the last digits of your card)

Golden rule: Never click on links in emails. Go directly to the website by typing the URL.

Step 7: Enable continuous monitoring

Breaches happen constantly. The smart thing isn't to check your email once and forget, but to activate a system that warns you automatically.

With SecuryBlack you can:

Monitor your email 24/7
Receive instant alerts when you appear in a new breach
View your digital exposure score

Step 8 (if applicable): Report

In Spain, if you have been a victim of fraudulent use of your data:

INCIBE (017) — Cybersecurity helpline
National Police — Technological Investigation Brigade
Civil Guard — Telematic Crimes Group
AEPD — If the company that suffered the breach didn't notify you (GDPR obligation)

Quick checklist

[ ] Identify what data was leaked
[ ] Change compromised passwords
[ ] Change reused passwords on other services
[ ] Enable 2FA on critical services
[ ] Review suspicious activity on your accounts
[ ] Contact your bank if financial data was leaked
[ ] Enable continuous monitoring

The first step is knowing where you're exposed. Check your email for free with SecuryBlack and follow this guide for each breach you find.