What is Improper Neutralization of Data within (CWE-652)?

TL;DR: Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) (CWE-652) is a vulnerability where untrusted input is improperly sanitized in an XQuery query, leading to unauthorized data access or modification. Use parameterized queries and validate user inputs to prevent this.

What is Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)?

Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) (CWE-652) is a vulnerability where untrusted input used to construct an XQuery expression is not properly sanitized, allowing attackers to manipulate the query structure. As defined by the MITRE Corporation under CWE-652 and classified by the OWASP Foundation as Not directly mapped.

Quick Summary

Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) allows attackers to inject malicious data into an XQuery expression, leading to unauthorized access or modification of XML database content. Jump to: Overview · How It Works · Business Impact · Attack Scenario · Detection · Fixing

Jump to: Quick Summary · Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Overview · How Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Works · Business Impact of Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) · Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Attack Scenario · How to Detect Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) · How to Fix Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) · Framework-Specific Fixes for Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) · How to Ask AI to Check Your Code for Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) · Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Best Practices Checklist · Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) FAQ · Vulnerabilities Related to Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) · References · Scan Your Own Site

Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Overview

What: This vulnerability occurs when user input is improperly sanitized before being used in an XQuery expression.

Why it matters: Attackers can manipulate the query to retrieve or modify sensitive data, compromising confidentiality and integrity.

Where it occurs: In applications that dynamically construct XQuery expressions based on untrusted inputs.

Who is affected: Developers using XML databases and XQuery for data retrieval and manipulation are at risk.

Who is NOT affected: Systems where user input does not influence the construction of XQuery queries or those employing robust validation mechanisms.

How Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Works

Root Cause

The root cause lies in the improper handling of untrusted inputs used to construct an XQuery expression. When such data is not properly sanitized, attackers can inject malicious content that alters query behavior.

Attack Flow

1. An attacker identifies a vulnerable application endpoint accepting user input.
2. The attacker crafts a payload designed to manipulate the structure of an XQuery expression.
3. The crafted payload is submitted through the vulnerable endpoint.
4. The untrusted input is incorporated into an XQuery expression without proper sanitization.
5. The manipulated query retrieves or modifies sensitive data from the XML database.

Prerequisites to Exploit

• User-provided input influences the construction of an XQuery expression.
• Insufficient validation and sanitization mechanisms are in place.

Vulnerable Code

def get_data(user_input):
    xquery = f"for $x in collection('{user_input}') return $x"

This code is vulnerable because it directly incorporates untrusted user input into an XQuery expression without proper sanitization.

Secure Code

def get_data(user_input):
    validated_input = validate_and_escape_user_input(user_input)
    xquery = f"for $x in collection('{validated_input}') return $x"

The secure code ensures that the user-provided input is properly sanitized and validated before being used in an XQuery expression.

Business Impact of Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)

Confidentiality

• Attackers can retrieve sensitive information stored in XML databases.
• Unauthorized access to confidential data leads to potential breaches.

Integrity

• Malicious queries may alter or delete critical data, compromising system integrity.

Availability

• Exploitation could lead to denial of service by corrupting database structures.

Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Attack Scenario

1. An attacker discovers a vulnerable endpoint accepting user input.
2. The attacker crafts an XQuery payload designed to retrieve sensitive data.
3. The crafted payload is submitted through the application’s API.
4. The untrusted input manipulates the structure of an XQuery expression.
5. Sensitive information from the XML database is retrieved and exfiltrated.

How to Detect Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)

Manual Testing

• Test endpoints accepting user inputs with crafted payloads designed to manipulate XQuery expressions.
• Verify that input sanitization mechanisms are correctly implemented.

Automated Scanners (SAST / DAST)

Static analysis can identify code patterns where untrusted inputs are directly used in XQuery expressions. Dynamic testing involves submitting malicious payloads to detect real-time vulnerabilities.

PenScan Detection

PenScan’s automated scanners, such as ZAP and Wapiti, actively test for this vulnerability by injecting crafted payloads into application endpoints.

False Positive Guidance

A finding is likely a false positive if the input validation mechanisms effectively sanitize all potential malicious content before constructing XQuery expressions.

How to Fix Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)

• Use parameterized queries to separate data from query logic.
• Implement strict validation and sanitization for user inputs.
• Reject or escape potentially harmful characters in input data.
• Employ robust mechanisms to ensure proper handling of untrusted inputs.

Framework-Specific Fixes for Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)

Python

def get_data(user_input):
    validated_input = validate_and_escape_user_input(user_input)
    xquery = f"for $x in collection('{validated_input}') return $x"

How to Ask AI to Check Your Code for Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)

Review the following Python code block for potential CWE-652 Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) vulnerabilities and rewrite it using parameterized queries: [paste code here]

Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) Best Practices Checklist

✅ Use parameterized queries to separate data from query logic. ✅ Implement strict validation and sanitization for user inputs. ✅ Reject or escape potentially harmful characters in input data. ✅ Employ robust mechanisms to ensure proper handling of untrusted inputs.

Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) FAQ

How does XQuery Injection work?

An attacker can manipulate user input to alter the structure of an XQuery query, leading to unauthorized data access or modification.

Why is it important to validate user input in XQuery queries?

Validating and sanitizing user-provided data prevents attackers from injecting malicious commands into XQuery expressions.

Can you show me a real-world example of XQuery Injection?

An attacker could inject an XQuery expression like “for $x in collection(‘sensitive’) return $x” to retrieve sensitive information from the XML database.

How can I detect XQuery Injection vulnerabilities in my code?

Automated scanners and manual testing with specific payloads help identify instances where user input is improperly sanitized before being used in XQuery queries.

What are some best practices for preventing XQuery Injection?

Always use parameterized queries to separate data from query logic, and validate all inputs according to strict rulesets that reject or escape potentially harmful characters.

How can I fix an existing XQuery Injection vulnerability in my application?

Implement input validation to ensure user-provided data is safe before incorporating it into XQuery expressions. Use parameterized queries where possible.

What are the common consequences of XQuery Injection attacks?

Attackers may gain unauthorized access to sensitive information stored within XML databases, leading to potential data breaches and compliance violations.

Vulnerabilities Related to Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’)

| CWE | Name | Relationship | |—|—|—| | CWE-943 | Improper Neutralization of Special Elements in Data Query Logic (ChildOf) | Child Of |

References

• MITRE
• NVD

Scan Your Own Site

Manual code review catches what you know to look for. An automated scan catches what you didn’t. Scan your own website using PenScan to find Improper Neutralization of Data within XQuery Expressions (‘XQuery Injection’) and other risks before an attacker does.