Firefox Monitor shows if your personal information was lost in a hack

Mozilla's service can help you decide which passwords need changing.

Stephen Shankland Former Principal Writer
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Stephen Shankland
2 min read
Mozilla Firefox icon logo

A Mozilla Firefox sticker

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Mozilla has launched a service called Firefox Monitor to check if your personal data was compromised in one of those all-too-common data breaches.

The service, based on the Have I Been Pwned service from security expert Troy Hunt, lets you type in your email address and find out if your account was among the hundreds of millions involved with hacks of Yahoo, LinkedIn, Equifax and other sites. Firefox Monitor also lets you sign up with your email address for alerts of future hacks, Mozilla announced Tuesday.

Finding out your account was affected by some corporate hack doesn't make your stolen data private again. But it still can be useful knowledge for figuring out which passwords you should change or how much you want to trust a particular company. It can also be a good motivation if you're nerving yourself to install a password manager or sign up for dual-factor authentication.

Mozilla's service doesn't offer much beyond what's already at Have I Been Pwned, but Firefox is a much better recognized brand name. And let's face it, most people don't know how to pronounce "pwned" much less figure out whether the term applies to them.

Mozilla began testing the Firefox Monitor service in June.

How about password checking?

Hunt also offers a service called Pwned Passwords where you can check to see if an actual password you use is among the 517,238,891 he's collected so far from real-world data breaches.

That sounds like the kind of data that could be useful for steering you clear of bad passwords when you're signing up for a new service, but Mozilla wouldn't comment specifically on whether it plans something like that. It does plan to expand beyond Firefox Monitor today.

"This is the first phase of Firefox Monitor to help all consumers be more aware of when they are involved with data breaches. We plan to have more features rolled out in the next couple of months for Firefox," Mozilla said in a statement.

Oh, and for the record, pwned is pronounced "poned," rhyming with "phoned."

First published September 25, 6 a.m. PT.

Update, 6:22 a.m. PT: Adds Mozilla comment about password checking.

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