Multiple users across the internet are reporting a serious issue with Steams servers. Users are stated they have logged only to be given access to other users accounts with their personal information displayed. Some users have stated being able to make purchases with the owners credit card, but that has yet to confirmed.
Valve have already proceeded to take down the store, and the website is now unavailable and returns and error. The security whole in questions has yet to be detailed, but Reddit user ARoyaleWithCheese has offered a very sensible theory that puts blame on Valve’s caching-server – whereas users account pages are actually being cached, when that’s a big no-no. This cached pages are their offered to users to just so happen to connect to that specific server, and in-turn gives the users control of the session, however, reports state this does NOT give users control of the users acccount, and merely display their information. Not a good thing none the less.
There has been no official word from Valve regarding the issue or when it may be fixed. Users still have access to their library’s but the store and site are down until this issue is resolved.
Update 1
The Steam Store has returned and the website is now live again. Still not word from Vable, but being Christmas day, a few phone calls our probably being made to relevant staff to put some decent PR spin on this.
Update 2
Vavle have released the following statement – confirmed the cache of account pages was the issue.
Steam is back up and running without any known issues,” a Valve spokesperson told GameSpot. “As a result of a configuration change earlier today, a caching issue allowed some users to randomly see pages generated for other users for a period of less than an hour. This issue has since been resolved. We believe no unauthorized actions were allowed on accounts beyond the viewing of cached page information and no additional action is required by users.
Update 3
A few days have passed since the wide spread Steam issue, and we now finally have a detailed statement from Valve as to what exactly caused the issue.
On December 25th, a configuration error resulted in some users seeing Steam Store pages generated for other users. Between 11:50 PST and 13:20 PST store page requests for about 34k users, which contained sensitive personal information, may have been returned and seen by other users.
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.
If you did not browse a Steam Store page with your personal information (such as your account page or a checkout page) in this time frame, that information could not have been shown to another user.
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.
How it happened
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 2000% 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. The Steam Store remained down until we had reviewed all caching configurations, and we received confirmation that the latest configurations had been deployed to all partner servers and that all cached data on edge servers had been purged.
We will continue to work with our web caching partner to identify affected users and to improve the process used to set caching rules going forward. We apologize to everyone whose personal information was exposed by this error, and for interruption of Steam Store service.
Any users that had information exposed during the mishap will be contacted by Valve directly. The number of users affected are stated to be affected are around 34,000.
