Online payments site PayPal has been bitten by yet another cross-site scripting (XSS) bug that could be exploited by black hats to phish user passwords or possibly steal authentication cookies.

At time of writing, opening the link revealed a tainted page that opened a javascript window that read: "Fugitif was here another time." It worked flawlessly on Internet Explorer and Firefox. Using the excellent Firefox NoScript plug-in automatically blocks the page from loading, however.

XSS bugs remain one of the easier ways to subvert website security measures. They use manipulated URLs to inject unauthorized code or content into a trusted website to change its behavior. XSS exploits are able to bypass the so-called same-origin policy, which prevents cookies and other types of content set by one domain from being access or manipulated by a different address.

PayPal squashed the bug late Monday evening, several hours after this article was originally published. "As you know, PayPal's highest priority is the security of its payment service," a spokesman said. He said the company encourages people to responsibly disclose bugs. Guidelines are here. ®

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