How to find SQL injection point

SQL injection points usually appear in user input, such as forms, query strings, cookies, and HTTP headers. When identifying injection points, you need to pay attention to the following characteristics: User input directly enters SQL statements, single or double quotes, SQL keywords and special characters. Injection points can be identified by reviewing code, testing inputs, and using security tools. Protection measures include parameterized query, verification and purification of inputs, use of whitelists, implementing firewalls and intrusion detection systems.

How to identify SQL injection points

SQL injection is a common web application attack where attackers manipulate databases by injecting malicious SQL code into user input. To prevent SQL injection attacks, developers need to identify and protect all potential injection points.

Types of SQL injection points

SQL injection points can exist in a variety of user inputs, including:

• Form fields
• Query string parameters
• Cookies
• HTTP header

Methods to identify SQL injection points

The key to identifying SQL injection points is to find the following characteristics:

• User input goes directly to SQL statement: Without proper data verification or escape, an attacker can use user input to insert malicious SQL code.
• Single or double quotes: These characters are used to quote string values ​​and are common entry points for SQL injection.
• SQL keywords: Keywords such as SELECT, UPDATE, and DELETE represent queries or operations and require careful inspection.
• Special characters: such as semicolons (;), line breaks (\n), and backslash (\), which can be used to separate SQL statements or escape special characters.

Specific steps

To identify SQL injection points, follow these steps:

1. Review application code: Check the database interaction section and find where user inputs directly enter SQL statements.
2. Test user input: Enter special characters and SQL keywords to view the application's response. If the application does not process these inputs correctly, there may be injection points.
3. Using the Security Scan Tool: Automatically identify SQL injection points with tools such as OWASP ZAP or Acunetix.

Protect SQL injection points

After identifying SQL injection points, developers need to protect them by:

• Use parameterized queries or stored procedures: These techniques separate user input from SQL statements to prevent malicious input from affecting queries.
• Verify and clean user input: Use input validation rules to filter special characters and SQL keywords.
• Use whitelist: Only specific input values ​​are allowed, blocking malicious input.
• Implement firewalls and intrusion detection systems: monitor abnormal activities and block potential attacks.

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