Five days and countless angry Reddit threads later, Valve has finally issued a statement about the caching issue that occurred last Friday—what happened, how many people were affected, and what Valve’s doing now.
You can find the full statement here, but the gist of it? It’s exactly what everyone thought happened, a.k.a. when hit with a DDOS attack on Christmas morning, someone accidentally pushed some bad code that caused a caching error of private info.
Or, as Valve puts it:
“Early Christmas morning (Pacific Standard Time), the Steam Store was the target of a DoS attack which prevented the serving of store pages to users. Attacks against the Steam Store, and Steam in general, are a regular occurrence that Valve handles both directly and with the help of partner companies, and typically do not impact Steam users. During the Christmas attack, traffic to the Steam store increased 2,000 percent over the average traffic during the Steam Sale.
In response to this specific attack, caching rules managed by a Steam web caching partner were deployed in order to both minimize the impact on Steam Store servers and continue to route legitimate user traffic. During the second wave of this attack, a second caching configuration was deployed that incorrectly cached web traffic for authenticated users. This configuration error resulted in some users seeing Steam Store responses which were generated for other users. Incorrect Store responses varied from users seeing the front page of the Store displayed in the wrong language, to seeing the account page of another user.
Once this error was identified, the Steam Store was shut down and a new caching configuration was deployed.”
What’s the damage?
According to Valve, 34,000 users were affected by the caching error—a paltry amount compared to Steam’s 125 million users, but still a sizable breach of personal information. Still, it’s nowhere near the size of the PlayStation Network breach that happened in 2011 which exposed data on 77 million users.
As for what was exposed Valve said: “The content of these requests varied by page, but some pages included a Steam user’s billing address, the last four digits of their Steam Guard phone number, their purchase history, the last two digits of their credit card number, and/or their email address. These cached requests did not include full credit card numbers, user passwords, or enough data to allow logging in as or completing a transaction as another user.”
You don’t need to panic yet. First of all, if you didn’t go on Steam on Christmas, your account details are safe by default. Other than that, “Valve is currently working with our web caching partner to identify users whose information was served to other users, and will be contacting those affected once they have been identified. As no unauthorized actions were allowed on accounts beyond the viewing of cached page information, no additional action is required by users.”
The presence of the phrase “web caching partner” seemingly indicates the screw-up arose from a third-party outside Valve—although that, of course, doesn’t absolve Valve of blame. Best you can do is hope you’re not one of the unlucky few.
This story, "Valve blames a partner for Christmas Day outage, which exposed data for 34,000 users" was originally published by PCWorld.