Use-after-free vulnerability in Blink, as used in Google Chrome before 38.0.2125.101, allows remote attackers to cause a denial of service or possibly have unspecified other impact via crafted JavaScript code that triggers a widget-position update that improperly interacts with the render tree, related to the FrameView::updateLayoutAndStyleForPainting function in core/frame/FrameView.cpp and the RenderLayerScrollableArea::setScrollOffset function in core/rendering/RenderLayerScrollableArea.cpp.