Hundreds of thousands of URLs have been compromised—at the time of writing, 694,000—in an enormous and indiscriminate SQL injection attack. The attack has modified text stored in databases, with the result that pages served up by the attacked systems include within each page one or more references to a particular JavaScript file.

The attack appears to be indiscriminate in its targets, with compromised machines running ASP, ASP.NET, ColdFusion, JSP, and PHP, and no doubt others. SQL injection attacks, which exploit badly-written Web applications to directly perform actions against databases, are largely independent of the technology used to develop the applications themselves: the programming errors that allow SQL injection can be made in virtually any language. The underlying cause is a programmer trusting input that comes from a Web page—either a value from a form, or a parameter in a URL—and passing this input directly into the database. If the input is malformed in a particular way, the result is that the database will run code of the attacker's choosing.

 In this case, the injected SQL is simply updating text fields within the database, to make them include an extra fragment of HTML. This HTML in turn loads a JavaScript from a remote server, typically "http://lizamoon.com/ur.php" or more recently, "http://alisa-carter.com/ur.php." Both domain names resolve to the same IP address, and presently that server is not functional, leaving browsers unable to load the malicious script when they visit infected pages. Previously, it contained a simple script to redirect users to a fake anti-virus site.

ARS Technica has the details HERE!