How to Tell if Your Personal Information Has Been Leaked
Most data leaks don't come with a warning email. By the time you notice unusual activity, your details may have been circulating for months. KNOMI helps Australians understand whether their personal information has been exposed and what to do about it before it turns into fraud or identity theft.
The quiet signs of a leak
Most exposures show up as small, easily dismissed signals: a wave of spam to an email you rarely use, login codes you didn't request, password-reset emails for services you never signed up for, or new contacts adding you on social.
On its own each signal is noise. Together they're a pattern — someone is testing your credentials across the web.
Run the checks KNOMI uses
Start with a breach check on every email address you use. KNOMI's free breach tool tells you which known breaches contain your address and what data was exposed. Pair that with a credit report from Equifax, illion or Experian — Australians are entitled to one free report a year, and recent enquiries are a fast way to spot identity misuse.
Then check the basics: your MyGov inbox for unexpected activity, your phone bill for a SIM-swap, and your bank statements for low-dollar test transactions, which scammers use before larger withdrawals.
Quick exposure checklist
- Run a breach check on every email address
- Pull a free Equifax / illion / Experian credit report
- Review MyGov, ATO and Centrelink activity
- Look for small unfamiliar transactions
- Confirm no unknown SIMs are linked to your number
What to do if you find something
Change the exposed password immediately and anywhere else you reused it. Turn on multi-factor authentication. If financial accounts are affected, put a ban or freeze on your credit file with all three agencies — it's free and stops new accounts being opened in your name.
If you're unsure what to do next, that's when KNOMI Cyber steps in. We map your exposure, guide the lockdown, and put an evidence pack together so reports to police, ReportCyber, or your bank actually land.
Frequently asked questions
Is my data on the dark web?
If your email has ever appeared in a major breach (LinkedIn, Canva, Optus, Medibank…) then yes, parts of your data are circulating. The KNOMI breach tool shows exactly which datasets your address is in.
Does changing my password fix a leak?
It closes one door. It doesn't undo the exposure of personal details like your date of birth or address. That's where credit bans and KNOMI's identity-monitoring guidance matter.
How often should I check?
Run a breach check quarterly, pull a credit report at least yearly, and turn on alerts for new logins on email, banking and MyGov.