The details of more than 400,000 user accounts have leaked onto the Internet in Sweden, following a series of attacks that have affected about 60 websites.

The hacking scandal started to get attention on Tuesday, when a Twitter account belonging to Swedish politician William Petz ä ll was used to publish passwords to email accounts belonging to some prominent journalists. Petz ä ll, who is currently undergoing treatment for addiction, denied that he had anything to do with it, and said that his Twitter account had been hijacked. The account was subsequently closed.

The source of the passwords turned out to be blogging site Bloggtoppen.se, which was vulnerable to an SQL injection attack. Its user database, which included details for approximately 94,000 accounts, was published back in September on a site called Flashback, and then distributed via Twitter, as well.

"The site has been closed until further notice," Bloggtoppen founder Jimmy Holmlund told Computer Sweden. He wasn't aware that an attack had taken place until the passwords were published via Petz ä ll's Twitter account.

On Wednesday, account details from another 57 sites were publicized, bringing the number of affected accounts to 180,000. As well as another 210,000 accounts from Gratisbio.se, which was hacked this summer, but the database with user names and passwords was made public on Tuesday evening, according to Computer Sweden.

The intrusion is one of the largest to ever take place in Sweden, based on the number of accounts affected.

In January 2008, virtual community Bilddagboken was also hacked. At that time, 235,000 accounts came in the wrong hands. Then, as now, the repercussions became bigger because users repeatedly used the same password, which made it very easy for attackers to break into, for example, email accounts using the leaked data, according to Computer Sweden.

This article is based on reports from Linus Larsson and Marcus Jerr ä ng of Computer Sweden, an IDG publication.

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