eBay is one of the most successful Internet-only ventures of all time, so it's not surprising that it has come under near-constant attack by fraudsters and hackers. In the latest attempt, a hacker logged on to the eBay Trust and Security forums and pretended to post as 1,200 separate users, making it appear as if he had actually logged in with each user's account. The posts contained the users' names, contact information, and credit card numbers.

That done, the hacker posted a video of his exploits on YouTube to celebrate his "achievement" (the video has subsequently been taken down). In response, eBay and LiveWorld—the third-party software firm that operates eBay's web-based forums—took the entire Trust and Security forum offline while they looked into the problem. The forum was taken down 90 minutes after the posts first hit the Web and was put back online later that day.

eBay issued an official statement on its eBay Chatter forum, stating that while the posts appeared to contain credit card information, the posted numbers did not correspond to credit card information that eBay had on file for those users. Nevertheless, the user names and contact information were accurate, and eBay claims they are attempting to get in contact by phone with each of the 1,200 users to ensure that they can protect themselves from any attempts at hijacking their accounts. At this time, eBay is unclear as to whether or not the accounts have been fully compromised. It is also not certain that only these 1,200 accounts are affected.

While the original posts and the YouTube video showing the list of names have been removed from the Web, an eBay member has grabbed as many of the account names as possible and posted them on a personal web site so that people can easily check to see if their account was one of the original 1,200. So far, the operator of this list has not been asked by eBay to take it down.

While this particular attack may not have revealed customers' credit card information, there are plenty of fraudsters about who are trying their hardest to scam people out of their money: a helpful eBay forum member even posted a list of an astonishing 36 common scams currently being perpetrated against eBay users. Most of these involve social manipulation and phishing scams rather than direct attack, but clearly they are effective: videos of hacked accounts posting over 60,000 items for bid show what the bad guys are likely to do once they have your account information. It's always a good idea to practice skeptical computing, but eBay users should take even greater care to ensure that they are not taken in by any of these scams.

An eBay representative did not return our request for a comment in time for publication.