Web Services are web-based applications made available for web users or
remote Web-based programs. In order to promote interoperability, they publish
their interfaces in the so-called WSDL file and allow remote call over the
network. Although Web Services can be used in different ways, the industry
standard is the Service Oriented Architecture Web Services that doesn't rely on
the implementation details. In this architecture, communication is performed
through XML-based messages called SOAP messages. However, those messages are
prone to attacks that can lead to code injection, unauthorized accesses,
identity theft, etc. This type of attacks, called XML Rewriting Attacks, are
all based on unauthorized, yet possible, modifications of SOAP messages. We
present in this paper an explanation of this kind of attack, review the
existing solutions, and show their limitations. We also propose some ideas to
secure SOAP messages, as well as implementation ideas