AdultFriendFinder, which calls itself "one of the largest sex hookup, dating, chat, sexy matches and adult friends sites in the world" was hacked last month, revealing personal information for 412 million accounts across multiple sites.
ZDNet reports the data stolen goes back to 1996 and includes usernames, passwords and email addresses. The fact that the data is 20 years old means AdultFriendFinder didn't delete old accounts from its servers after users shut them down.
The hack also hit Cams.com, Stripshow.com and Penthouse.com.
In 2015, hackers stole personal data from four million AdultFriendFinder accounts, including sexual preferences. And Ashley Madison was hacked in July 2015, compromising data from 30 million users.
So who did it?
It's not yet clear who carried out the hack. The security researcher who discovered the leak blamed a Russian hacking site.
AdultFriendFinder vice president Diana Ballou said it is reviewing the breach and has fixed the vulnerability that hackers used to access the code.
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