Hackers made available personal data of around 4 million users of a major dating website. Media reports say that details of users’ sexual preferences were leaked, including data on whether people are gay or straight or seeking extramarital affairs, as well as their email addresses, usernames and dates of birth.

It is reported that hackers published information relating to users of Adult FriendFinder on the dark web – this is a part of the worldwide web that Google doesn’t index. After posting data, the intruders to the system claimed on the forum that they wanted to hit victims with spam emails.

The website in question accounts for 63 million users all over the world. The Adult FriendFinder introduces itself as a “thriving sex community”, where users can share sensitive sexual data. In result of the hack, the data of 3.9m users has been leaked, including those people who requested the service to delete their accounts and all relevant information.

One of the affected users confirmed that he has been targeted with virus-infected emails after his data leaked, even though he didn’t even use the site. He did try to get in and had to provide his data to do so, because a user couldn’t get into the Adult FriendFinder without handing over information. He then deleted his account and believed that the data was erased, but dating websites are not always as secure as they meant to be.

The industry experts think that after the spam email campaign, the hackers will also use the obtained information to find blackmail targets, as they have names, dates of birth and addresses – everything to target specific individuals.

The Adult FriendFinder explained that it is investigating the leak and cooperating with law enforcement. The company informed that a comprehensive investigation with the help of 3rd-party forensics experts had already been started.