The users were alerted to the fact that something was amiss with the appearance of a promoted discussion thread within which a site offering cracks for games was being promoted. Suspicions that the breach went beyond common defacement begun to pop up as users began sharing on the forum that they were receiving spam emails promoting the very same site.
It didn't take long for the company to react and take down the site, but didn't comment on the happenings at first. Even Steam's game servers were taken offline, which alarmed expectant users as they can only play the game online if they have access to the platform.
Fortunately, the game servers were back online in time for today's launching of the game, and an explanation of the situation was finally offered by Valve's co-founder Gabe Newell.
Addressing Steam and Steam Forum users, he confirmed that the forum defacement happened on the evening of Sunday, November 6, and that the intrusion went far beyond that.
"We learned that intruders obtained access to a Steam database in addition to the forums. This database contained information including user names, hashed and salted passwords, game purchases, email addresses, billing addresses and encrypted credit card information," he wrote. "We do not have evidence that encrypted credit card numbers or personally identifying information were taken by the intruders, or that the protection on credit card numbers or passwords was cracked. We are still investigating."
Also confirming that the company is aware only of a few forum accounts having been compromised, he announced that all forum users will be required to change their passwords the next time they log in, and advised those who used that password on other accounts to change it.
He pointed out that to the best of their knowledge, no Steam accounts have been compromised, but suggested to users to consider changing those passwords as well.
"We don’t have evidence of credit card misuse at this time. Nonetheless you should watch your credit card activity and statements closely," he finally advised, and said that forums will be opened again as soon as possible.
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