Online dating website, which encourages those married to have relationships outside their marriage, has been hacked, putting at risk personal information of as much as 37 million users.

A hacker, or a group of hackers known as The Impact Team, has taken responsibility for the attack. The Impact Team claims that it has access to the company's financial records, proprietary information and has threatened to reveal users' sexual fantasies.

According to the hackers, this latest hack is a response to the company's alleged false promises. The website charges a fee of $19 for a "Full Delete" option in case users wish to erase their profile on the website. However, hackers say that this information is not deleted from the database, adding that the company made $1.7 million in revenue last year from this option.

The group has released a manifesto, demanding that ALM take down Ashley Madison and Established Men permanently.

So far, maps of internal company servers, employee network account information, company bank account data and salary information has been leaked, reported Brian Krebs on his security blog.

This latest data breach comes two months after its sister site, owned by Toronto based firm, Avid Life Media (ALM), was also hacked.

Meanwhile, Noel Biderman, CEO, Avid Life Media said that they are very close to identifying those responsible for the attack. "I've got their profile right in front of me, all their work credentials. It was definitely a person here that was not an employee but certainly had touched our technical services," he told Krebs.

Interestingly, one of the leaked documents reveal that a data compromise was one of the worst fears of chief technology officer, Trevor Stokes. When asked "in what area would you hate to see something go wrong", Stokes answered, "I would hate to see our systems hacked and/or the leak of personal information."