Indeed, LinkedIn claims on its website to have over 433 million registered members.

Attempts to contact the seller failed, but the administrators of LeakedSource, a data leak indexing website, claim to also have a copy of the data set and they believe that the records do originate from the 2012 LinkedIn breach.

Only 117m accounts have passwords and we suspect the remaining users registered using FaceBook or some similarity."

Hashing is a one-way operation that generates unique, verifiable cryptographic representations of a string that are called hashes.

When the 6.5 million LinkedIn password hashes were leaked in 2012, hackers managed to crack over 60 percent of them.

LinkedIn users who haven't changed their passwords in a long time, are advised to do so as soon as possible.

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