Use-after-free vulnerability in the V8 bindings in Blink, as used in Google Chrome before 37.0.2062.94, allows remote attackers to cause a denial of service or possibly have unspecified other impact by leveraging improper use of HashMap add operations instead of HashMap set operations, related to bindings/core/v8/DOMWrapperMap.h and bindings/core/v8/SerializedScriptValue.cpp.