SQL Injection Vulnerability: What is it and how to stay protected?

• SQL injection vulnerability impacts web applications that use SQL database such as MySQL, Oracle, SQL server, etc
• SQL injection vulnerability could allow attackers to gain complete access to the data of a database.

What is SQL Injection Vulnerability - SQL Injection vulnerability is the most commonly exploited vulnerability that could allow an attacker to insert a malicious SQL statement into a web application database query.

What does it impact - SQL injection vulnerability impacts web applications that use SQL database such as MySQL, Oracle, SQL server, or others SQL-based databases.

Why do attackers exploit it?

Attackers exploit SQL injection vulnerability to gain unauthorized access to the compromised database that contains sensitive data and to bypass application security mechanisms. Attackers could also add, modify, and delete records in the compromised database.

SQL injection vulnerability could allow attackers to gain complete access to the data of a database.

How do attackers exploit it?

• To exploit the SQL injection vulnerability, attackers must first identify vulnerable user inputs within a web application.
• Attackers then inject malicious SQL statements in the database of the web application.
• Attackers could then compromise the database and gain access to the contents of the database such as credentials, user data, personal information, financial information, confidential data, etc.

What are the types of SQL Injection vulnerabilities?

There are four types of SQL Injection vulnerabilities such as Error-based SQL injection, Boolean-based SQL injection, Time-based SQL injection, and Out-of-Band SQL injection.

• Error-based SQL injection - Error-based SQL injection vulnerability could allow attackers to retrieve information from database errors.
• Boolean-based SQL injection - If there are no error messages on the web application, then attackers look for other indications and leverage them to extract information from the vulnerable application. Such a method is known as Boolean-based SQL injection.
• Time-based SQL injection - In this case, attackers set sleep time and instruct it to wait on sleep mode for the stated amount of time. If the web app is vulnerable, it will take a longer time to load, if not it will load quickly. This way attackers will determine the vulnerable application and will extract information.
• Out-of-Band SQL injection - This could allow attackers to retrieve database information by leveraging out-of-band techniques such as sending the data directly from the database to the attacker-controlled system.

Examples of SQL injection vulnerabilities

Attackers exploited the SQL injection vulnerability in the Kaseya VSA plugin to infect the Managed Service Providers (MSPs) with Gandcrab ransomware. The vulnerability existed in the Kaseya VSA plugin for the ConnectWise Manage software, a professional services automation (PSA) product used by IT support firms.

Attackers exploited the two-year-old vulnerability in a software package used by MSPs to gain access to vulnerable networks and deploy the GandCrab ransomware on the MSP clients’ endpoints.

How to stay protected?

• In order to stay protected from such attacks, it is best to sanitize all input and validate input.
• It is recommended to turn off the visibility of database errors in web pages and web applications.
• Researchers recommend developers to whitelist input validation and use prepared statements with parameterized queries.
• It is best to install a good web application firewall to stay protected from such exploits.