Failure to Sanitize Data within XQuery Expressions ('XQuery Injection')
Weakness ID: 652 (Weakness Base)Status: Incomplete
+ Description

Description Summary

The software uses external input to dynamically construct an XQuery expression used to retrieve data from an XML database, but it does not sufficiently sanitize that input. This allows an attacker to control the structure of the query.

Extended Description

The net effect is that the attacker will have control over the information selected from the XML database and may use that ability to control application flow, modify logic, retrieve unauthorized data, or bypass important checks (e.g. authentication).

+ Time of Introduction
  • Implementation
+ Applicable Platforms



+ Common Consequences

Controlling application flow (e.g. bypassing authentication)


Information disclosure

+ Likelihood of Exploit


+ Enabling Factors for Exploitation

XQL queries are constructed dynamically using user supplied input that has not been sufficiently validated.

+ Observed Examples
From CAPEC 84: An attacker can pass XQuery expressions embedded in otherwise standard XML documents. Like SQL injection attacks, the attacker tunnels through the application entry point to target the resource access layer. The string below is an example of an attacker accessing the accounts.xml to request the service provider send all user names back. doc(accounts.xml)//user[name='*'] The attacks that are possible through XQuery are difficult to predict, if the data is not validated prior to executing the XQL.
+ Potential Mitigations

Use parameterized queries. This will help ensure separation between data plane and control plane.

Properly validate user input. Reject data where appropriate, filter where appropriate and escape where appropriate. Make sure input that will be used in XQL queries is safe in that context.

+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness BaseWeakness Base91XML Injection (aka Blind XPath Injection)
Development Concepts (primary)699
Research Concepts (primary)1000
+ Relationship Notes

This weakness is similar to other weaknesses that enable injection style attacks, such as SQL injection, command injection and LDAP injection. The main difference is that the target of attack here is the XML database.

+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
WASC46XQuery Injection
+ Content History
Submission DateSubmitterOrganizationSource
2008-01-30Evgeny LebanidzeCigitalExternal Submission
Modification DateModifierOrganizationSource
2008-09-08CWE Content TeamMITREInternal
updated Common Consequences, Relationships
2008-10-14CWE Content TeamMITREInternal
updated Description, Name, Relationship Notes
2009-05-27CWE Content TeamMITREInternal
updated Name
2009-10-29CWE Content TeamMITREInternal
updated Common Consequences
Previous Entry Names
Change DatePrevious Entry Name
2008-10-14Unsafe Treatment of XQuery Input
2009-05-27Failure to Sanitize Data within XQuery Expressions (aka 'XQuery Injection')