Unravelling the Layers of Client-Side SQL Injection Vulnerabilities in Mobile Applications

Introduction:

In the dynamic landscape of web and mobile applications, security remains a paramount concern. In this blog, we will delve into the world of client-side SQL injection vulnerabilities, exploring various types and tools used by attackers, and providing practical examples to illustrate the risks involved.

Mobile applications lacking proper data validation and sanitization are vulnerable to exploitation through various attacks unique to mobile environments, such as SQL injection, command injection, and cross-site scripting (XSS) attacks. For further information on this topic, kindly visit the OWASP link provided below.

• https://owasp.org/www-project-mobile-top-10/2023-risks/m4-insufficient-input-output-validation

Prerequisites:

To effectively unravel the layers of client-side SQL injection vulnerabilities in mobile applications, you need a solid understanding of the following prerequisites:

1. SQL (Structured Query Language):

• Strong understanding of SQL, including query structure, syntax, and common database operations.
• Knowledge of how databases are used in the context of mobile applications.

2. Client-Side Vulnerabilities:

• Familiarity with client-side vulnerabilities, especially those related to mobile applications.
• Understanding of how user input is handled and processed on the client side.

3. Database Systems:

• Understanding of different database systems commonly used in mobile applications (e.g., SQLite, MySQL, or PostgreSQL).
• Knowledge of how data is stored, retrieved, and manipulated in these database systems.

4. Mobile App Security Frameworks:

• Awareness of security frameworks and best practices specific to mobile application development.
• Knowledge of tools and frameworks used for securing mobile applications.

For a deeper dive into the realm of Mobile Security, we encourage you to explore our extensive collection of informative blogs & e-books:

• https://payatu.com/e-books/device-setup-and-barriers/
• https://payatu.com/blog/need-to-know-android/
• https://payatu.com/blog/penetrate-the-protected-component-in-android-part-0/
• https://payatu.com/blog/penetrate-the-protected-component-in-android-part-2/

By acquiring these prerequisites, you’ll be better equipped to delve into the complexities of client-side SQL injection vulnerabilities in mobile applications and effectively unravel their layers.

Let’s discuss first what is a database?

A database is a way of electronically storing collections of data in an organised manner. A database is controlled by a DBMS, which is an acronym for Database Management System, DBMSs fall into two camps Relational or Non-Relational, the focus of this room will be on Relational databases. Some common ones you’ll come across are MySQL, Microsoft SQL Server, Access, PostgreSQL, and SQLite.

The terms “Client-side SQL injection” and “Server-Side SQL injection vulnerability” refer to different aspects of a security issue related to SQL injection attacks. Let’s clarify the differences:

1. Server-Side SQL Injection Vulnerability:
   • Definition: SQL injection is a type of security vulnerability that occurs when an attacker is able to manipulate an SQL query by injecting malicious SQL code.
   • Location: This vulnerability can exist on both the client-side and the server-side of a web or mobile application.
   • Impact: Exploiting an SQL injection vulnerability can lead to unauthorized access, data manipulation, and potentially the execution of arbitrary SQL commands on a database.
2. Client-Side SQL Injection:
   • Definition: Client-side SQL injection specifically refers to situations where the vulnerability exists on the client-side of an application, meaning that user inputs on the client-side are manipulated to inject malicious SQL code.
   • Location: The issue occurs in the client-side code, which is typically the code running on the user’s device (e.g., web browsers, mobile apps).
   • Example: In an Android app, if user inputs are not properly validated or sanitized before being used in SQL queries, it can lead to client-side SQL injection.

Various ways that can expose mobile applications to client-side SQLi vulnerabilities:

Client-side SQL injection vulnerabilities in mobile applications mainly occur when an application improperly handles user input on the client-side, leading to potential SQL injection attacks. However, there might be other factors as well that contribute to or help exploit the client-side SQLi.

Here are different client-side SQL injection vulnerabilities commonly found in mobile applications:

1. Insecure Data Storage:
   o Description: If sensitive data such as SQL statements or database credentials are stored insecurely on the client-side, an attacker with access to the device may extract and manipulate this information.
   o Example: Extracting stored SQL queries or credentials from the mobile app’s local storage.

public class InsecureDataStorageExample {

    public static void main(String[] args) {
        // Insecurely storing sensitive data (e.g., database credentials) in a file
        storeCredentialsInsecurely("db-credentials.txt", "username:admin,password:secret");
    }

    private static void storeCredentialsInsecurely(String fileName, String credentials) {
        try {
            File file = new File(fileName);
            FileWriter fw = new FileWriter(file);
            BufferedWriter writer = new BufferedWriter(fw);

            // Writing sensitive information to the file
            writer.write(credentials);

            // Closing the resources
            writer.close();
            fw.close();

            System.out.println("Credentials stored insecurely in " + fileName);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

2. Insecure Direct Object References (IDOR):
   o Description: If the mobile application exposes direct references to database objects, an attacker may manipulate these references to execute unintended SQL queries.
   o Example: Modifying a URL parameter to access unauthorized database records.

public class InsecureIDORExample {

    // Simulating a simple database with user records
    private static Map<Integer, String> userDatabase = new HashMap<>();

    public static void main(String[] args) {
        // Adding some sample user records
        userDatabase.put(1, "Alice");
        userDatabase.put(2, "Bob");
        userDatabase.put(3, "Charlie");

        // Insecure code: Exposing direct references to database objects (IDOR vulnerability)
        int userId = getUserIDFromRequest(); // Assume this comes from an untrusted source, like a URL parameter
        String userName = getUserFromDatabase(userId);
        System.out.println("User ID: " + userId + ", User Name: " + userName);
    }

    // Simulates extracting user ID from an untrusted source (e.g., URL parameter)
    private static int getUserIDFromRequest() {
        // Insecure: Simulating user input, which can be manipulated by an attacker
        return Integer.parseInt("4"); // An attacker could manipulate this value to access unauthorized records
    }

    // Simulates a database query based on user ID
    private static String getUserFromDatabase(int userId) {
        // Insecure: Directly using the provided user ID without proper authorization checks
        return userDatabase.get(userId);
    }
}

3. Unsanitized Input Fields & Lack of Input Validation:
   o Description: Failing to validate and sanitize user inputs allows attackers to inject malicious SQL code.
   o Example: Submitting crafted data in input fields or parameters that are not properly validated.

public class VulnerableCode {

    public static void main(String[] args) {
        String userInput = getUserInput(); // Assume this method gets user input from a form or another source

        // Vulnerable SQL query with no input validation
        String query = "SELECT * FROM users WHERE username = '" + userInput + "'";

        try (Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydatabase", "username", "password");
             PreparedStatement statement = connection.prepareStatement(query);
             ResultSet resultSet = statement.executeQuery()) {

            // Process the result set...

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    private static String getUserInput() {
        // Assume this method retrieves user input from a form or another source
        return "maliciousUser' OR '1'='1";
    }
}

public class VulnerableCode {
    public static void main(String[] args) {
        // Vulnerable code: Concatenating strings without proper validation

        // Simulating user input (can come from UI, API, etc.)
        String userInput = "'; DROP TABLE users; --";

        // Constructing SQL query using string concatenation (vulnerable)
        String query = "SELECT * FROM users WHERE username = '" + userInput + "'";

        try {
            // Connecting to the database (Assuming a SQLite database for simplicity)
            Connection connection = DriverManager.getConnection("jdbc:sqlite:mydatabase.db");
            Statement statement = connection.createStatement();

            // Executing the SQL query
            ResultSet resultSet = statement.executeQuery(query);

            // Processing the results (not shown for simplicity)

            // Closing resources
            resultSet.close();
            statement.close();
            connection.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

5. Caching and Local Data Storage:
   o Description: Cached or locally stored data may contain SQL queries or sensitive information that an attacker could manipulate.
   o Example: Modifying cached data on the device to alter SQL queries executed by the mobile app.

public class VulnerableCache {

    private static Map<String, String> userCredentialsCache = new HashMap<>();

    public static void main(String[] args) {
        // Simulating storing user credentials in the local cache
        storeCredentials("user123", "password123");

        // Simulating an attacker modifying cached data
        manipulateCachedData();
    }

    private static void storeCredentials(String username, String password) {
        userCredentialsCache.put(username, password);
    }

    private static void manipulateCachedData() {
        // Attacker modifies the cached password for "user123"
        userCredentialsCache.put("user123", "evilPassword");

        // Simulating using the cached data for authentication
        authenticateUser("user123", "evilPassword");
    }

    private static void authenticateUser(String username, String password) {
        String storedPassword = userCredentialsCache.get(username);

        if (password.equals(storedPassword)) {
            System.out.println("Authentication successful!");
        } else {
            System.out.println("Authentication failed!");
        }
    }
}

6. Insecure Transport of Data:
   o Description: If data transmitted between the mobile app and the server is not properly secured, attackers may intercept and modify the SQL queries in transit.
   o Example: Intercepting network traffic and modifying SQL queries before they reach the server.

public class InsecureDataTransport {

    public static void main(String[] args) {
        try {
            // Insecure HTTP connection, vulnerable to interception
            String apiUrl = "<http://example.com/api>";
            URL url = new URL(apiUrl);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();

            // Assume data to be sent is in JSON format
            String jsonData = "{\\"username\\": \\"admin\\", \\"password\\": \\"password123\\"}";

            // Enable input/output streams for sending data
            connection.setDoOutput(true);
            connection.setRequestMethod("POST");
            connection.setRequestProperty("Content-Type", "application/json");

            // Send data to the server
            OutputStream outputStream = connection.getOutputStream();
            outputStream.write(jsonData.getBytes());
            outputStream.flush();

            // Read the response from the server
            BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String line;
            StringBuilder response = new StringBuilder();
            while ((line = reader.readLine()) != null) {
                response.append(line);
            }
            reader.close();

            // Do something with the server response
            System.out.println("Server response: " + response.toString());

            // Close the connection
            connection.disconnect();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Practical Demonstration:

For this practical approach to exploit the vulnerability, we are using some vulnerable applications,

Client-side SQLi Vulnerability Exploitation in the BugBazaar Application:

Below are the prerequisites to exploit the vulnerability,

• A rooted Android device (Physical or Emulator)
• Android Debug Bridge (ADB)
• An application decompiler (JADX)

Step 1: Install the BugBazaar Android application on the device.
Step 2: Launch the application & log in with valid credentials.
Step 3: Navigate to the My Orders Section
Step 4: We can see here some Order Values of 101 & 102.

Also, we have a search button to get a particular order from the order list.

Now Decompile the BugBazaar application with the JDAX decompiler tool to better understand the My Order activity code.

From the above code snippet, we have observed, that this SQL query is essentially searching for records in the order_history table where the order_id column contains the value specified by the orderID variable, and the COLUMN_ORDER_ID column does not contain the specific value ‘ORDER-9’. It is important to note that constructing queries by concatenating strings, as shown here, can be prone to SQL injection attacks as this code doesn’t use parameterized queries or prepared statements.

In this BugBazaar application, there is one more activity found which is vulnerable to client-side SQLi.

Now navigate to the Addresses Section, as shown in the screenshot below, we have the addresses saved by the user & a default one. Also, there is an option to save new addresses & search addresses.

From the decompiled addresses code, we can analyse,

From the above code snippet, we have observed that the SQL query is designed to retrieve records from the addresses table where the nickname column contains a specified substring (provided by the nickname variable) and the COLUMN_NICKNAME column does not contain the substring ‘super_secret0x’. It’s important to note that constructing SQL queries by concatenating strings like this can make the code vulnerable to SQL injection attacks. Let’s try to exploit the issue with the payload.

Client-side SQLi Vulnerability Exploitation of the Sieve Application:

Download the Sieve application from GitHub (https://github.com/as0ler/Android-Examples/blob/master/sieve.apk) & install it on the testing device.

Upon launching the application, a welcoming screen will be displayed. To proceed, input the password “Password12345678” into both fields and then click the “Submit” button.

Navigate to the “Enter PIN” page and input the PIN “1234” into both fields. Afterwards, click the “Submit” button, following the provided illustration.

On the following page, input the password in the “Password12345678” field, and then click the “Sign In” button, as illustrated below.

As we find client-side SQLi vulnerabilities, we will also focus on content providers of the application.

Enumerating Content Providers from Source Code

Locate the displayed content providers in the code (AndroidManifest.xml file), which include DBContentProvider and FileBackupProvider. Both of these providers are currently marked for export.

Discovering URIs

To leverage content providers, acquiring the URIs directing to their content is necessary. In the JADX decompiler tool, navigate to File and select Open to load the application file.

Subsequently, locate and click on the Search icon, which is highlighted in red in the image below.

Locate occurrences of “content://” as illustrated below and identify three URIs.

Retrieving Passwords

Execute the below command in the terminal or command prompt,

adb shell content query --uri content://com.mwr.example.sieve.DBContentProvider/Passwords

The reply includes both a username and an email address, while the password is stored in an encrypted Binary Large Object (BLOB), as illustrated below.

Retrieving Keys

Execute the below command in the terminal or command prompt,

adb shell content query --uri content://com.mwr.example.sieve.DBContentProvider/Keys

Displaying an error message indicating a lack of permission to view the content.

Let’s understand the Path Permission on the above error,

Review the permissions assigned to the DBContentProvider. As indicated in the following code snippet, the permissions are specified through the following line:

The “path” permissions are explained, as shown below. These permissions only apply if the exact path ends in /Keys.

Now let’s try to retrieve Keys/ by executing the below command, in the terminal or command prompt,

adb shell content query --uri content://com.mwr.example.sieve.DBContentProvider/Keys/

We can see the password, as shown below.

Triggering an SQL Error

adb shell content query --uri content://com.mwr.example.sieve.DBContentProvider/Passwords/ --projection "'"

The response indicates the presence of an SQL injection vulnerability, as evidenced by the “SQLiteException: unrecognized token” error highlighted in the above image.

Retrieving Table Names

Execute the below command in the terminal or command prompt,

adb shell
content query --uri content://com.mwr.example.sieve.DBContentProvider/Passwords/ --projection "* FROM SQLITE_MASTER WHERE type='table';--"

Three tables are present, which include “Passwords” and “Key,” as illustrated below.

Retrieving Passwords

Execute the below command in the terminal or command prompt,

adb shell
content query --uri content://com.mwr.example.sieve.DBContentProvider/Passwords/ --projection "* FROM Passwords;--"

We can see the user credentials below,

Mitigation:

To mitigate client-side SQL injection vulnerabilities in mobile applications, developers should implement secure coding practices, validate, and sanitize user inputs, use parameterized queries, and follow best practices for secure data storage and transmission.

Regular security assessments and code reviews can also help identify and address potential vulnerabilities.

Mitigating client-side SQL injection vulnerabilities in mobile applications involves implementing various security measures to prevent attackers from injecting malicious SQL code. Here are some key mitigation processes:

1. Input Validation and Sanitization:
   • Validate and sanitize all user inputs on the client-side before processing or sending them to the server.
   • Use input validation routines to ensure that data adheres to expected formats and values.
   • Employ whitelisting to allow only known safe characters and patterns.

public class VulnerableCode {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter your username: ");
        String username = scanner.nextLine();

        // Vulnerable point: No input validation or sanitization
        System.out.println("Welcome, " + username + "!");
    }
}

In this vulnerable code snippet, the program directly accepts user input for the username without any validation or sanitization, leaving it susceptible to various attacks such as SQL injection, cross-site scripting (XSS), and other security vulnerabilities.

Now, let’s complement this code with input validation and sanitization:

public class SecureCode {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter your username: ");
        String username = scanner.nextLine();

        if (isValidUsername(username)) {
            // Safe point: Input validation passed
            System.out.println("Welcome, " + username + "!");
        } else {
            System.out.println("Invalid username. Please enter a valid username.");
        }
    }

    private static boolean isValidUsername(String username) {
        // Input validation routine: Only allow alphanumeric characters and underscores
        String regex = "^[a-zA-Z0-9_]+$";
        Pattern pattern = Pattern.compile(regex);
        Matcher matcher = pattern.matcher(username);
        return matcher.matches();
    }
}

In the secure code snippet, a simple input validation routine is added to the isValidUsername method, which checks whether the username contains only alphanumeric characters and underscores. This is just a basic example, and in a real-world scenario, you might need more comprehensive validation based on your application’s requirements. Always tailor your validation to the specific context and data being processed.

2. Parameterized Statements:
   o Utilize parameterized statements or prepared statements when interacting with the database.
   o Avoid constructing SQL queries by concatenating strings with user input.
   o Parameterized queries help separate user input from the SQL query itself, preventing injection attacks.

Vulnerable Code:

public class VulnerableExample {

    public static void main(String[] args) {
        String username = "user1'; DROP TABLE users; --";
        String password = "password123";

        // Vulnerable code: Constructing SQL query by concatenating strings
        String sqlQuery = "SELECT * FROM users WHERE username='" + username + "' AND password='" + password + "'";

        try (Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/database", "user", "password");
             PreparedStatement preparedStatement = connection.prepareStatement(sqlQuery)) {

            // Execute the query (this is vulnerable to SQL injection)
            // ...

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

Secure (Compliant) Code:

public class SecureExample {

    public static void main(String[] args) {
        String username = "user1'; DROP TABLE users; --";
        String password = "password123";

        // Secure code: Using parameterized statement to prevent SQL injection
        String sqlQuery = "SELECT * FROM users WHERE username=? AND password=?";

        try (Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/database", "user", "password");
             PreparedStatement preparedStatement = connection.prepareStatement(sqlQuery)) {

            // Set parameters in the prepared statement
            preparedStatement.setString(1, username);
            preparedStatement.setString(2, password);

            // Execute the query (safe from SQL injection)
            ResultSet resultSet = preparedStatement.executeQuery();

            // Process the result set
            while (resultSet.next()) {
                // Handle results
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

In the secure code snippet, the parameters (username and password) are set using the setString method of the PreparedStatement object, which ensures that user input is treated as data rather than executable SQL code. This helps prevent SQL injection attacks.

3. Secure Coding Practices:
   o Educate developers about secure coding practices, especially regarding the handling of user input in SQL queries.
   o Emphasize the importance of input validation, proper escaping, and the use of secure coding libraries.

Vulnerable Code:

public class VulnerableCode {

    public ResultSet getUserData(String username, String password) {
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;

        try {
            // Assume that 'url', 'user', and 'password' are properly initialized
            connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydatabase", "user", "password");
            statement = connection.createStatement();

            // Vulnerable SQL query concatenating user input
            String query = "SELECT * FROM users WHERE username='" + username + "' AND password='" + password + "'";
            resultSet = statement.executeQuery(query);

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                if (resultSet != null) resultSet.close();
                if (statement != null) statement.close();
                if (connection != null) connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        return resultSet;
    }

    public static void main(String[] args) {
        VulnerableCode vulnerableCode = new VulnerableCode();
        ResultSet result = vulnerableCode.getUserData("user1", "password123");

        // Process the result set (this is just an example, don't do this in real code)
        // ...

    }
}

Secure Code:

public class SecureCode {

    public ResultSet getUserData(String username, String password) {
        Connection connection = null;
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;

        try {
            // Assume that 'url', 'user', and 'password' are properly initialized
            connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydatabase", "user", "password");

            // Use a prepared statement to safely handle user input
            String query = "SELECT * FROM users WHERE username=? AND password=?";
            preparedStatement = connection.prepareStatement(query);
            preparedStatement.setString(1, username);
            preparedStatement.setString(2, password);

            resultSet = preparedStatement.executeQuery();

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                if (resultSet != null) resultSet.close();
                if (preparedStatement != null) preparedStatement.close();
                if (connection != null) connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        return resultSet;
    }

    public static void main(String[] args) {
        SecureCode secureCode = new SecureCode();
        ResultSet result = secureCode.getUserData("user1", "password123");

        // Process the result set (this is just an example, don't do this in real code)
        // ...
    }
}

In the secure code, I replaced the Statement with a PreparedStatement to use parameterized queries. This helps prevent SQL injection by automatically handling the escaping of user input. Always prefer parameterized queries over string concatenation when dealing with user inputs in SQL queries.

4. Use Object Relational Mapping (ORM) Frameworks:
   o Consider using ORM frameworks that automatically handle the translation of object-oriented code to SQL queries.
   o ORM frameworks often provide a higher level of abstraction, reducing the risk of SQL injection vulnerabilities.

Vulnerable Code (without ORM):

public class UserRepository {
    public User getUserById(int userId) {
        Connection connection = // Get a database connection (omitted for brevity)

        // Vulnerable code: Concatenating user input directly into the SQL query
        String sql = "SELECT * FROM users WHERE user_id = " + userId;

        try (PreparedStatement statement = connection.prepareStatement(sql)) {
            ResultSet resultSet = statement.executeQuery();
            
            if (resultSet.next()) {
                // Process and return the user data
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

        // Handle no user found or other cases
        return null;
    }
}

Compliant Code (using Hibernate ORM):

public class UserRepository {
    public User getUserById(int userId) {
        Session session = // Get a Hibernate session (omitted for brevity)

        // Compliant code: Using Hibernate Query with parameters to avoid SQL injection
        String hql = "FROM User WHERE userId = :userId";
        Query<User> query = session.createQuery(hql, User.class);
        query.setParameter("userId", userId);

        User user = query.uniqueResult();
        
        // Handle no user found or other cases
        return user;
    }
}

In the compliant code using Hibernate, the query is parameterized, and Hibernate takes care of handling user input securely, preventing SQL injection vulnerabilities. Always prefer using ORM frameworks like Hibernate to interact with databases as they provide a higher level of abstraction and help mitigate common security risks.

5. Use of Database Encryption:
   Database encryption is a security measure that involves transforming stored data within a database into a ciphertext using various encryption algorithms. This helps protect sensitive information from unauthorized access or exposure in the case of a security breach. Encryption ensures that even if someone gains access to the underlying database, the data remains unreadable without the appropriate decryption key.

6. Network Encryption:
   o Ensure that data transmitted between the mobile app and the server is encrypted using secure protocols (e.g., HTTPS).
   o Encryption helps protect against Man-in-the-Middle (MitM) attacks, preventing attackers from intercepting and modifying data.

7. Secure Data Storage:
   o Avoid storing sensitive information, such as SQL queries or database credentials, on the client side.
   o If client-side storage is necessary, use secure storage mechanisms and encrypt sensitive data.

8. Regular Security Audits and Testing:
   o Conduct regular security audits and penetration testing on the mobile application to identify and address vulnerabilities.
   o Use automated security testing tools to scan for potential SQL injection vulnerabilities in the code.

9. Code Reviews:
   o Implement a thorough code review process to catch and address potential security flaws.
   o Encourage peer reviews to ensure that multiple sets of eyes examine the code for security issues.

10. Security Headers:
    o Implement security headers in the mobile app to mitigate certain types of injection attacks.
    o For example, Content Security Policy (CSP) headers can help prevent the execution of injected scripts.

11. User Authentication and Authorization:
    o Implement strong user authentication and authorization mechanisms to control access to sensitive data and actions.
    o Ensure that users have the least privilege necessary to perform their tasks.

By incorporating these mitigation processes into the development lifecycle of a mobile application, developers can significantly reduce the risk of client-side SQL injection vulnerabilities. It’s essential to stay informed about emerging threats and update security measures accordingly.

Conclusion:

To summarize, “SQL injection vulnerability” is a broad term that encompasses the overall susceptibility of an application to SQL injection attacks. This vulnerability can exist on both the client-side and the server-side. “Client-side SQL injection” is a specific case where the vulnerability is on the client-side, indicating that the manipulation of user inputs occurs in the client-side code.

Developers need to be aware of and address SQL injection vulnerabilities on both the client and server-sides to ensure the security of their applications. Best practices include using parameterized queries or prepared statements, validating, and sanitizing user inputs, and staying informed about emerging security threats.