On November 6 of last year the forums of Valve’s Steam gaming platform were vandalized, followed by an intrusion on a Steam user database containing usernames, hashed and salted passwords, billing and email addresses, game purchase transcripts, and encrypted credit card info.

The company started an investigation and required Steam users to change their forum passwords, which are different from Steam account passwords. There was no evidence that the encrypted credit card information or any other information was compromised.

Gabe Newell has issued a new update on the nature of the intrusion and advises Steam users to watch their credit card activity and to keep using Steam Guard.

You can read his update in full after the break.

Dear Steam Users and Steam Forum Users

We continue our investigation of last year’s intrusion with the help of outside security experts. In my last note about this, I described how intruders had accessed our Steam database but we found no evidence that the intruders took information from that database. That is still the case.

Recently we learned that it is probable that the intruders obtained a copy of a backup file with information about Steam transactions between 2004 and 2008. This backup file contained user names, email addresses, encrypted billing addresses and encrypted credit card information. It did not include Steam passwords.

We do not have any evidence that the encrypted credit card numbers or billing addresses have been compromised. However as I said in November it’s a good idea to watch your credit card activity and statements. And of course keeping Steam Guard on is a good idea as well.

We are still investigating and working with law enforcement authorities. Some state laws require a more formal notice of this incident so some of you will get that notice, but we wanted to update everyone with this new information now.

Gabe