// Guides
Data leak — am I affected?
A data leak is the unauthorised disclosure of data — such as credentials — online. Leaked passwords are tried automatically across many services (credential stuffing). Checking and securing is therefore central.
Updated: 2026-06-19
Immediate steps
- 1Check whether your e-mail address appears in known leaks (e.g. HPI Identity Leak Checker, Have I Been Pwned).
- 2Change passwords of affected services — no reuse across accounts.
- 3Use a password manager so every account has its own password.
- 4Enable 2FA everywhere it is offered.
- 5Preserve unusual activity and login notifications (screenshots, timestamps).
- 6If online banking is affected: inform your bank and monitor accounts.
What not to do
- Do not keep using leaked passwords — not even slightly modified.
- Do not pay for “leak removal” offers — once leaked, data cannot be reliably deleted from the net.
- Do not ignore warnings — an old leak can be used for takeovers years later.
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Common questions
- What does a hit in the leak check mean?
- That your address appears in a known dataset. First change the passwords of the affected and most important services and enable 2FA.
- Can leaked data be deleted?
- No — once distributed, data cannot be reliably retrieved. Hardening and monitoring make sense, not paying for deletion promises.
- How often should I check?
- Regularly — or via ongoing monitoring that reports new hits automatically.