Steam users got a Christmas surprise on Friday when library and account details for other users started appearing where their own account information was supposed to be.

The service shut down briefly and the issue was fixed within an hour. Steam gatekeeper Valve Software is now trying to reassure users that their private information is safe, though the incident was at the very least disconcerting.

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The company says the issue sprung up after a "configuration change" on Valve's side created caching issues, causing temporarily stored data — normally used to speed up the Steam client's performance — to appear in places it shouldn't have. Sensitive details such as credit card numbers are automatically censored on user account pages, which mitigates the potential harm of someone having seen your personal data.

Yet some reports said users were able to see other people's email addresses and billing addresses.

"Steam is back up and running without any known issues," Valve told Game Informer in a statement. "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."

The issue arose at a tough moment, as Steam's annual "Winter Sale" is underway right now. These seasonal price cuts on games and other software are always popular moments among PC gamers, bringing heavier-than-normal traffic to the service. It's fortunate for Valve that the issue was addressed relatively quickly.

That said, there's never any harm in changing your password, especially if you haven't done so in a while. Valve has a variety of safeguards built into Steam for securing your account, as well as an extensive guide that offers tips on keeping your data safe from unfriendly eyes.