The IBM Stax XMLStreamWriter in the Web Services component in IBM WebSphere Application Server (WAS) 6.1 before 6.1.0.25 does not properly process XML encoding, which allows remote attackers to bypass intended access restrictions and possibly modify data via "XML fuzzing attacks" sent through SOAP requests.
Weaknesses in this category are related to the management of permissions, privileges, and other security features that are used to perform access control.