5 SQL Injection Testing Methods and Why to Automate Your Test
The SQL injection test is done to see if random data can be injected into the database and will be recognized by the system. Some malicious data can be placed on the database and will cause chaos in the whole system. Malicious data can be accepted even if it is not supposed to go through. Testers will check these vulnerabilities that they can determine through different SQL injection testing methods.
Table Of Contents
What is SQL Injection Testing?
SQL injection testing is a process of inserting data into an application to verify that user-controlled SQL queries can be run on a database. It is used to detect vulnerabilities in an application that could be exploited by malicious users to gain access to sensitive data. The goal of SQL injection testing is to identify and prevent malicious inputs from being accepted by the application.
It gives protection to all of the web applications that contain data and would need databases to work. The moment that the weaknesses of the SQL data are determined by hackers and other unauthorized users, the data can be compromised. They can be manipulated and changed. This will cause problems with how the web applications and web servers work.
5 SQL Injection Testing Methods
The testing methods are the following:
- Stacked Query Testing
- Error-Based Injection Testing
- Boolean-Based Injection Testing
- Blind Exploit Testing
- Time Delay Exploit Testing
All of these testing methods will be discussed more in detail.
Applications are not going to provide enough details whenever an error is detected. A tester should know how to do the different SQL injection testing methods to know the error and come up with the proper solution.
Stacked Query Testing
This method requires the testers to finish an SQL statement and create a new one. The main goal of this is to ensure that the stacked queries will not be supported by the applications that they are testing.
An attacker who uses this type of testing will use a semicolon to remove a whole statement in SQL. This allows the attacker to make changes to the data. It will allow the data to become more vulnerable. More statements can be placed in the database that will become favorable to the attacker.
Data Modification
An attacker would like to cause harm to the system to make it more vulnerable. The attacker will place statements to make further modifications. A password change is the most common thing to do to have better access to the whole system.
It will look like this:
1; UPDATE members SET password=’pwd’ WHERE username=’admin’
GENERATED QUERY.
SELECT * FROM products WHERE categoryid=1; UPDATE members SET password=’pwd’ WHERE username=’admin’
Terminate Statement
The goal of the attacker is to terminate the statements that are set in place that will prevent malicious attacks. When these statements are removed, it will be easier for the attacker to place other commands that will allow the data to become vulnerable.
It will look like this:
/*Malicious user input by attacker*/
1; DELETE FROM products
/*This example executes multiple statements*/
SELECT * FROM products WHERE productid=1; DELETE FROM products
Query Stacking
Query stacking is not the most common type of attack that hackers and attackers do because it does not always work. The database or the API that does not support this function will immediately stop the modification of the data.
The query stacking support will come in this form:
MySQL/PHP – Not supported (supported by MySQL for other APIs).
SQL Server/Any API – Supported.
Oracle/Any API – Not supported.
Adding SELECTs can become limited especially if multiple statements are being injected. Some of the statements will have results but will be ignored by the system. Others might trigger error messages. This is a bit tricky to use because the attacker should know some basic information about the data before pushing through with the attack. The lack of the needed data will make the attack unsuccessful.
Calling A Procedure
Database management systems are supposed to have functions that will make the development simple. There should also be new functionalities that will further protect the data.
Calling a procedure means that the SQL attack is going to be more extreme. Doing this attack will cause an upset with the system. The whole operating system can be controlled. Making changes to the SQL statements will also become simpler.
This example will show how an SQL server-specific command can be used to control the operating system calls.
1; exec master..xp_cmdshell ‘DEL important_file.txt’
GENERATED QUERYSELECT * FROM products WHERE categoryid=1; exec master..xp_cmdshell ‘DEL important_file.txt’
An attack might stop the calls that the operating system will get. There are more complex attacks that can take control of the whole system. It will depend on the type of statements that will be used.
Error-Based Injection Testing
This is a type of SQL injection technique wherein testers need to check the error messages that will be released by the database. Some unauthorized users may try to find information from the error messages that they receive. This can compromise the security of the whole database. This can be prevented by testing what type of error messages will be displayed by the SQL. The internal errors should not be released to the users.
Boolean-Based Injection Testing
This is a test SQL injection that will require an SQL query to be sent to the database. The application will show a TRUE or FALSE result depending on the conditional statement set by the testers. This can be used to test the weaknesses of Boolean-based injection.
The goal of this type of testing is to make sure that any user input will not run as an SQL code. Attacks will be more common if this happens which is why this type of testing is always recommended.
Blind Exploit Testing
Some testers also refer to this as Out-of-Band exploit testing. A blind SQL injection is similar to the usual SQL injection but this time, the data will come from the database itself. Attackers will try to ask some true or false questions to learn more about how the database works.
This can be prevented by doing this type of testing. Out-of-band connections will be determined and fixed so that data from the database will not be retrieved by the attackers.
Time Delay Exploit Testing
This is a useful type of testing when dealing with blind SQL injection issues. This requires sending injected queries. The testers will be checking the response time of the database. If the condition is true, the response time will be delayed.
Manual vs Automated Testing
A company can only say that its website or app is secure once it knows all of the SQL vulnerabilities that need to be checked, are checked and fixed. SQL injection is common and can be done to get the stored data from apps and websites.
Once the data has been compromised or removed from the system, companies might need to stop their operations. It can hinder them from offering their best services to the users. This can only be prevented through frequent testing by testers.
The type of testing done by testers can be broadly classified as Manual and Automated:
| Manual | Automated |
| Testers need to check the various features of apps and websites to look for all the errors, bugs, and other anomalies. | Testers can come up with frameworks that will enable them to create test scripts. These test scripts can automate the user actions that can test the app or the website. |
| The accuracy might not be at its best because of the possibility of human errors. | Higher accuracy is expected since the testing will be mainly computer-based. |
| This will require a lot of time to do especially when it needs to be done on a large scale. | The time spent on testing the same amount of data can be done in a shorter time. |
| User experience can be greatly improved with the use of manual testing. This is going to check the user experience of the user which can guarantee that users will be happier using apps and websites that have been tested manually. | There is no guarantee that user experience can be greatly improved with the use of automated testing. |
| Manual testing is best used for the following:Exploratory TestingUsability TestingAd-hoc Testing | Automated testing is best used for the following:Regression TestingLoad TestingPerformance TestingRepeated Execution |
Automated SQL Injection Testing
One of the main reasons why people prefer automated testing for SQL injection is the time that they will spend doing it. A lot of web applications and websites contain sensitive data so testing these manually will be prone to issues and human errors.
Some tools can be used to make testing easier. The tools can help create the right framework so that test scripts can be created. Templates will be easier to test against different types of attacks. The easier the potential attacks can be detected, the safer the website or the web application is going to be.
Just remember that even if there are tools that can make the work easier, you still need the right testers to help you. The tools are not always reliable. You need professionals who can always double-check things for you. An IT expert will provide the best help.
Related Security Activities
Different activities should be done to ensure that data is always protected. One important security activity is to always check the physical security of the SQL server. This means that you have to limit the number of people who can access the data center where the database is located. The data center can only be accessed by a select group of trusted people.
Other related security activities to protect the data are the following:
- Make sure that the operating system is always protected. Use a supported operating system for your web application and web servers. Database servers should also not be allowed to have internet access.
- Disable some of the components of the SQL server that are not being used. Unused portions can be the weak spots of the server. They can be targeted by hackers.
- Configure a server that will be focused on a different port. A default port is used for the database connections that you have on your server. You can create a different server that can listen in on the other ports that are not commonly used. It can help keep the server safer.
- Make adjustments to the SQL server. This means that those who would attempt to check specific types of data are required to go through database authentications. Some only need to go through Windows authentication. Some need to go through both Windows and SQL authentication.
How to Avoid SQL Injection Vulnerabilities?
Database programmers need to restrict the database code and so much more to prevent possible SQL attacks. These are the steps to take:
- Filter the database inputs: Look for malicious codes that come from users.
- Limit the available database code: Unauthorized users may begin to attempt the exploration of the database procedures. Limiting this ahead of time will make a huge difference in the success of their plans.
- Restrict access to the database: Prevent unauthorized people from entering the database of the web application or the website.
- Keep the database well-maintained: Make sure that the database is always fully patched and always updated. The more well-maintained the database is, the harder it will be to access.
- Always monitor the application, the database, and all the user-generated inputs: Most malicious attempts can be detected by doing this often.
These steps can be done properly by experts who know the process of doing SQL injection tests.
How to Review Code for SQL Injection Vulnerabilities?
An SQL injection attack can make malicious SQL commands make a lot of changes to the whole database of the web application or the website. To review the code, you can do the following:
- Exclude some specific symbols – This means that there are some codes with symbols that do not need to run anymore. You can also set the allowed symbol name formats.
- Exclude some of the specific types and some of the derived types – You can add the key-value pair to your project file.
- Look for some of the potential violations by running the pseudo-code examples – You can come up with this by using the right tools. Experts will also know how to run this properly.
How to Test for SQL Injection Vulnerabilities?
- The first step is to always remember the goal of any SQL attack which is to hack the database of the web application or website.
- The quotes should be tried for single code and double codes.
- Make sure that the query is always true.
- Check for some results that will indicate that there is an attack that is happening such as the following:
- See if the page is loading properly.
- There are no messages that will indicate if there are errors or if the codes are successful.
- There are success messages that will appear for malicious codes.
If there are inappropriate messages that will appear for any particular field, this is a sign that there is a possible malicious attack. It is best to get the technical support of data experts to avoid potential issues in the long run.
Summary
The clearer your view is of what an SQL injection is, the easier it will be to prevent any malicious attacks. The database should always be maintained and updated to prevent potential losses that may happen if an attack becomes successful. Any system vulnerabilities that will be known by the users can cause problems for the company’s reputation. It is going to be hard to make users trust the company again.
Frequently Asked Questions
What is an SQL injection example?
An example of SQL injection is retrieving hidden data. This means that the SQL query can be modified to provide additional results. Let’s say that the user is using a shopping app. If it would click on one category, the browser will request a certain URL to load. This will make the app request an SQL query. All of the items that are supposed to be under the category will be displayed to the user.
Is SQL injection used in security testing?
SQL injection is known to be a common way to attack a web application or website. There are times when it can also be used for security testing. There are malicious codes that will be used in place of the usual codes just to see if it would push through and if the server will start to execute the code.
What are some best SQL injection tools?
Different SQL injection tools can be used for various purposes. Netsparker is a tool that can be used for web vulnerability management solutions. This can check if some web vulnerabilities should be checked and tested soon. Another tool is the jSQL injection. This is a Java-based tool that can be used to check the database of other nearby servers.
Data server professionals should know how to test SQL injection correctly so that vulnerabilities can be easily detected.
