Everything is vulnerable in the cyberspace. According to a recent survey conducted on a group of Indian hackers, it was identified that the main vulnerability in the Indian websites is SQL injection or SQLi. Even in the last month, Indusface’s AppTrana observed 2,773,000 SQL injection attacks. Despite being a simpler form of attack, SQLi can expose sensitive data, enable unauthorized access to user information, delete or alter databases, execute administrative tasks with far-reaching consequences such as commands issued to the operating system to shut down or even for identity spoofing. Any of these can cause massive financial and almost irreparable reputational damage to businesses.
It is therefore important to understand the functioning of SQLi attacks and ways to prevent them.
What are SQL Injection Attacks?
It is important to first understand the importance of SQL. Structured Query Language or SQL was developed in the 1970s as a programming language that enabled communication or query databases to request information and data access. SQL queries are received by databases and accordingly commands like data retrieval, deletion of a record, alterations to the database including updates are carried out.
SQL Injection attacks
At times, attackers manage to inject malicious code by altering SQL queries to manipulate the backend databases. These attacks are known as SQL injection attacks. Typically, attackers take advantage of user input sections such as login, contact or query forms, comments to inject the malicious SQL code that affects the execution of genuine, pre-defined SQL commands. As a result, attackers are able to access information that wasn’t supposed to be displayed. According to OWASP, these attacks are highly severe.
The Causes of SQLi
SQL injection vulnerabilities enable attackers to interfere with the SQL queries made to the database of a website or web application. Usage of legacy code or hasty programming can cause such vulnerabilities. Most SQLi attacks can be categorized into 3 broad segments:
● In-band SQLi: Cybercriminals launch attacks and extract results through the same communication channels. This is a very simple and most widely used attack vector with two sub-types known as Error-based SQLi and Union-based SQLi.
● Inferential or Blind SQLi: Such attacks are carried out to understand database behaviour through observation of responses and server behaviour. Even though these are slower to execute, they can be as damaging as any other SQLi attacks. Boolean and Time-based SQLi are the sub-types of this category.
● Out-of-band SQLi: This option is used when attackers are unable to use the same communication channel for attacking and gathering information or in case the server is too unstable or slow to execute such actions. To execute the out-of-band SQL injection attacks, there are certain features that the database servers need to have.
How does this work?
Normally, attackers would scan applications to discover vulnerabilities through different methods such as crawlers and bots. Upon identification of vulnerability, attackers inject arbitrary code into the SQL queries and access the data targeted.
The attackers try out variations of SQLi through common SQL injection commands to discover which ones can be executed by the database. This technique allows them to repeatedly access the information desired. Depending on the purpose, an attacker might stop after extracting the information needed or continue to repeatedly exploit the vulnerabilities as long as they exist.
Bot-driven SQL injection
Nowadays, SQL injection attacks are often automated. AI-powered bots are being used to intelligently automate the scan and search efforts, and can also automatically attack when they identify vulnerability. Toolkits containing such bot armies are available and sometimes attackers get bot as a service too.
Ways to prevent SQL Injection Attack
Scanning and Pen-testing to identify SQL Injection vulnerabilities
Intelligent scanning tools can detect not just SQLi, but all other known vulnerabilities and when tuned, can also identify other logical vulnerabilities present in the website or web application. Regular scanning can help users identify and secure those vulnerabilities. That’s why opting for pen testing by trusted experts is a great way to understand the vulnerabilities and the impact and will eventually help in resolving them.
Managed Web Application Firewall (WAF)
Futuristic, intuitive WAFs can filter out malicious SQL queries and other such threats faced by the application. These solutions use a combination of signature, pattern, and behaviour analysis, customized whitelisting and blacklisting protocols, global threat intelligence, IP reputation history, and other security processes to prevent SQL injection attacks with minimum false positives.
Comprehensive security
Since AI-bots are now driving SQLi attacks, it is crucial to deploy comprehensive security solutions that are powered by AI automation.
Other options
Even though the below-listed practices are not fool-proof, they are among the most effective deterrents of SQL injection attacks.
● Validating all user inputs to filter out illegitimate and malicious SQL code.
● Using parameterized queries/ prepared statements/ stored procedures to ensure that SQL elements in user fields are not used as actual SQL queries.
● Following least privilege policies and limiting contributor permissions.
● Only displaying generic error messages.
● Encryption and secure storage of sensitive data.
The crux
Over the years, SQL injection attacks have hurt numerous businesses including Heartland Payment Systems and Epic Games etc. Technological evolution has further helped attackers mount sophisticated and more damaging assaults on databases. Therefore, bolstering the security of your websites and applications by using comprehensive, intuitive, and automated solutions is the best defence against the SQLi.