The product does not properly neutralize special 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.

Primary

Implementation
REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Confidentiality
Integrity
Availability
Execute Unauthorized Code or Commands
Read Application Data
Modify Application Data

Automated Static Analysis
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
High

Implementation
Input Validation

Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
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. This 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, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

XML injection (aka Blind Xpath injection)

A2
Injection Flaws
CWE More Specific

A6
Injection Flaws
CWE More Specific

23
XML Injection

SFP24
Tainted input to command

Allowed
This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

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.
In vulnerability theory terms, this is a representation-specific case of a Data/Directive Boundary Error.
Under-reported. This is likely found regularly by third party code auditors, but there are very few publicly reported examples.

PLOVER
2006-07-19
Draft 3
2006-07-19

Eric Dalci
Cigital
2008-07-01
updated Time_of_Introduction

Veracode
2008-08-15
Suggested OWASP Top Ten 2004 mapping

CWE Content Team
MITRE
2008-09-08
updated Relationships, Other_Notes, Taxonomy_Mappings

CWE Content Team
MITRE
2008-10-14
updated Maintenance_Notes, Other_Notes, Theoretical_Notes

CWE Content Team
MITRE
2010-02-16
updated Taxonomy_Mappings

CWE Content Team
MITRE
2010-06-21
updated Description, Relationships

CWE Content Team
MITRE
2011-06-01
updated Common_Consequences

CWE Content Team
MITRE
2012-05-11
updated References, Relationships

CWE Content Team
MITRE
2012-10-30
updated Potential_Mitigations

CWE Content Team
MITRE
2014-02-18
updated Related_Attack_Patterns

CWE Content Team
MITRE
2014-06-23
updated Relationships

CWE Content Team
MITRE
2014-07-30
updated Relationships, Taxonomy_Mappings

CWE Content Team
MITRE
2015-12-07
updated Relationships

CWE Content Team
MITRE
2017-11-08
updated Applicable_Platforms, Modes_of_Introduction, References, Relationships

CWE Content Team
MITRE
2018-03-27
updated Relationships

CWE Content Team
MITRE
2019-06-20
updated Related_Attack_Patterns

CWE Content Team
MITRE
2020-02-24
updated Potential_Mitigations, Related_Attack_Patterns, Relationships

CWE Content Team
MITRE
2020-06-25
updated Potential_Mitigations

CWE Content Team
MITRE
2020-08-20
updated Relationships

CWE Content Team
MITRE
2020-12-10
updated Relationships

CWE Content Team
MITRE
2021-10-28
updated Relationships

CWE Content Team
MITRE
2023-01-31
updated Description

CWE Content Team
MITRE
2023-04-27
updated Detection_Factors, References, Relationships, Time_of_Introduction

CWE Content Team
MITRE
2023-06-29
updated Mapping_Notes

CWE Content Team
MITRE
2025-12-11
4.19
2025-12-11
updated Relationships, Weakness_Ordinalities