Firefox Monitor is an online service developed by

Mozilla Mozilla (stylized as moz://a) is a free software community founded in 1998 by members of Netscape. The Mozilla community uses, develops, spreads and supports Mozilla products, thereby promoting exclusively free software and open standards, w ...

, announced in June 2018, and launched on September 25 of that year. It informs users if their

email address An email address identifies an email box to which messages are delivered. While early messaging systems used a variety of formats for addressing, today, email addresses follow a set of specific rules originally standardized by the Internet Enginee ...

and

password A password, sometimes called a passcode (for example in Apple devices), is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of ...

s used have been leaked in

data breach A data breach is a security violation, in which sensitive, protected or confidential data is copied, transmitted, viewed, stolen or used by an individual unauthorized to do so. Other terms are unintentional information disclosure, data leak, info ...

es, using the database provided by

Have I Been Pwned? Have I Been Pwned? (HIBP; with " Pwned" pronounced like "poned", and stylized in all lowercase as "';--have i been pwned?" on the website) is a website that allows Internet users to check whether their personal data has been compromised b ...

(HIBP). Mozilla is also working with HIBP's creator,

Troy Hunt Troy Adam Hunt is an Australian web security consultant known for public education and outreach on security topics. He created Have I Been Pwned?, a data breach search website that allows users to see if their personal information has been co ...

. Despite the name, this service is not limited to Mozilla Firefox alone, but can be accessed as a website from all common browsers.

References

Further reading