Use-after-free vulnerability in the VisibleSelection::nonBoundaryShadowTreeRootNode function in core/editing/VisibleSelection.cpp in the DOM implementation in Blink, as used in Google Chrome before 40.0.2214.111 on Windows, OS X, and Linux and before 40.0.2214.109 on Android, allows remote attackers to cause a denial of service or possibly have unspecified other impact via crafted JavaScript code that triggers improper handling of a shadow-root anchor.