Severe vulnerability at eBay's website

Golem.de writes: The German security expert Micheal E. discovered the persistent cross-site scripting vulnerability on eBay's website about two months ago and said he reported it to Ebay immediately. Ebay ceased to answer his emails, after writing that they considered it a mostly harmless error. Micheal E. sent Golem.de a PoC demonstrating that the error that has not yet been fixed. An attacker can manipulate an official auctioning web page and insert Javascript code. By visiting the malicious web page the code is executed by the victim and could potentially be used by the attacker to to execute arbitrary actions in the victim's Ebay account and gain full control over it. There is probably no connection to the huge database theft reported a few days ago. The XSS flaw can only be used to attack one victim at a time.