XML injection

This section will cover two different perspectives on the use of XML in web applications:

• When the application performs searches in an XML file or XML database
• When the user submits XML formatted information to be parsed by the application

XPath injection

XPath is a query language for selecting nodes from an XML document. The following is the basic XML structure:

<rootNode> 
  <childNode> 
    <element/> 
  </childNode> 
</rootNode> 

An XPath search for element can be represented as follows:

/rootNode/childNode/element 

More complex expressions can be made, for example, an XPath query for a login page may look like the following:

//Employee[UserName/text()='myuser' And...