Double free vulnerability in IBM WebSphere Application Server (WAS) 6.1.0.x before 6.1.0.35 and 7.x before 7.0.0.15 allows remote backend IIOP servers to cause a denial of service (S0C4 ABEND and storage corruption) by rejecting IIOP requests at opportunistic time instants, as demonstrated by requests associated with an ORB_Request::getACRWorkElementPtr function call.