CWE-141: Improper Neutralization of Parameter/Argument Delimiters

What is Improper Neutralization of Parameter/Argument Delimiters?

• Overview: Improper Neutralization of Parameter/Argument Delimiters (CWE-141) occurs when a software application receives input that contains special characters or sequences that are not adequately sanitized or neutralized, allowing them to be misinterpreted as delimiters in commands or queries, potentially altering the intended logic or behavior of the downstream component.

• Exploitation Methods:

• Attackers can exploit this vulnerability by crafting input data that includes malicious delimiters to manipulate the execution flow.
• Common attack patterns include injecting unexpected argument separators in command execution or data queries, leading to command injection or SQL injection attacks.

• Security Impact:

• Direct consequences of successful exploitation include unauthorized command execution or data retrieval/modification.
• Potential cascading effects include data corruption, application crashes, or escalation of privileges.
• Business impact may involve data breaches, loss of customer trust, and regulatory compliance violations.

• Prevention Guidelines:

• Specific code-level fixes include validating and sanitizing all input data to remove or neutralize special delimiter characters before processing.
• Security best practices involve employing strict input validation and using parameterized queries or commands to separate data from control logic.
• Recommended tools and frameworks include static code analysis tools to detect improper delimiter handling and libraries that abstract away direct handling of command or query construction.

Corgea can automatically detect and fix Improper Neutralization of Parameter/Argument Delimiters in your codebase. [Try Corgea free today](https://corgea.app).

Technical Details

Likelihood of Exploit: Not specified

Affected Languages: Not Language-Specific

Affected Technologies: Not specified

Vulnerable Code Example

import sqlite3

def execute_query(query, params):
    # Vulnerable code: The params are directly interpolated into the SQL query,
    # which can lead to SQL injection if params contains malicious SQL code.
    connection = sqlite3.connect('example.db')
    cursor = connection.cursor()
    cursor.execute(query % params)  # {7} <-- Improper parameterization
    result = cursor.fetchall()
    connection.close()
    return result

# Example usage
# User input is directly used in the query, making it vulnerable to SQL injection
user_input = "'; DROP TABLE users; --"
execute_query("SELECT * FROM users WHERE username = '%s'", user_input)  # {10} 

How to fix Improper Neutralization of Parameter/Argument Delimiters?

Fixed Code Example

import sqlite3

def execute_query(query, params):
    # Fixed code: Use parameterized queries to safely pass user input as data
    # rather than executable code, preventing SQL injection.
    connection = sqlite3.connect('example.db')
    cursor = connection.cursor()
    cursor.execute(query, params)  # {7} <-- Proper parameterization
    result = cursor.fetchall()
    connection.close()
    return result

# Example usage
# User input is safely passed as a parameter, preventing SQL injection
user_input = "; DROP TABLE users; --"
execute_query("SELECT * FROM users WHERE username = ?", (user_input,))  # {11} 

In the fixed example, the query uses parameterized queries by passing the query and its parameters separately to cursor.execute(). This ensures that user input is treated as a parameter, not as part of the SQL command, thereby mitigating the risk of SQL injection.