A "malicious fraudster" used an eBay discussion forum yesterday to post confidential information about eBay users. The poster also published what may be eBay users' credit card numbers.

The incident, first reported by AuctionBytes.com, a technology news site that focuses on e-commerce, led eBay to shut down the forum - ironically, devoted to the discussion of security issues.

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Nichola Sharpe, an eBay spokeswoman, confirmed that yesterday morning someone the vendor describes as "a malicious fraudster" posted the names and contact information of 1,200 eBay members on the company's Trust & Safety discussion forum.

"This information could have been obtained as part of an account takeover. Since this time, our Trust and Safety team has been proactively addressing this situation," she said via email.

Along with members' information, the "fraudster" also posted what appear to be credit card numbers. However, if that's what they are, they don't match the ones eBay has on file for the members whose contact information was disclosed, Sharpe said.

"We are in the process of proactively contacting members by phone, so that if the information is valid somehow - regardless of how this fraudster acquired the information - these members can take the steps they need to take to protect themselves," Sharpe said.

The "fraudster" didn't obtain the information by breaching eBay's security systems, so eBay thinks the culprit stole the information via methods such as phishing, she said.

The company has posted more information in an official eBay blog post.

The incident, which eBay continues to monitor, has been broadly reported and commented on by eBay users on this long thread.

In its article, AuctionBytes reported being able to access the forum and view several posts before they were removed.

The posts included fields labeled 'Id verified' and "Store', along with a time-date stamp of the user registration, AuctionBytes reported, adding that it hasn't been able to verify the accuracy of the information viewed.