The software does not properly neutralizespecial elements that are used in XML, allowing attackers to modify the syntax, content, or commands of the XML before it is processed by an end system.
Within XML, special elements could include reserved words or characters such as "<", ">", """, and "&", which could then be used to add new data or modify XML syntax.
Time of Introduction
Architecture and Design
Technical Impact: Execute unauthorized code or
commands; Read application data; Modify application data
Strategy: Input Validation
Assume all input is malicious. Use an "accept known good" input
validation strategy, i.e., use a whitelist of acceptable inputs that
strictly conform to specifications. Reject any input that does not
strictly conform to specifications, or transform it into something that
When performing input validation, consider all potentially relevant
properties, including length, type of input, the full range of
acceptable values, missing or extra inputs, syntax, consistency across
related fields, and conformance to business rules. As an example of
business rule logic, "boat" may be syntactically valid because it only
contains alphanumeric characters, but it is not valid if the input is
only expected to contain colors such as "red" or "blue."
Do not rely exclusively on looking for malicious or malformed inputs
(i.e., do not rely on a blacklist). A blacklist is likely to miss at
least one undesirable input, especially if the code's environment
changes. This can give attackers enough room to bypass the intended
validation. However, blacklists can be useful for detecting potential
attacks or determining which inputs are so malformed that they should be
[REF-7] Mark Dowd, John McDonald
and Justin Schuh. "The Art of Software Security Assessment". Chapter 17, "XML Injection", Page 1069.. 1st Edition. Addison Wesley. 2006.
The description for this entry is generally applicable to XML, but the name includes "blind XPath injection" which is more closely associated with CWE-643. Therefore this entry might need to be deprecated or converted to a general category - although injection into raw XML is not covered by CWE-643 or CWE-652.