The WebCore::HTMLLinkElement::process function in WebCore/html/HTMLLinkElement.cpp in WebKit, as used in Apple Safari before 5.0.3 on Mac OS X 10.5 through 10.6 and Windows, and before 4.1.3 on Mac OS X 10.4; webkitgtk before 1.2.6; and possibly other products does not verify whether DNS prefetching is enabled when processing an HTML LINK element, which allows remote attackers to bypass intended a ...