One of the most common attack types, SQL Injection attacks (SQLi attacks) have far-reaching business impacts. A successful injection attack of this kind could lead to exposure of sensitive information, unauthorized viewing of user information, deletion or modification of the database, execution of administrative actions on the database, commands issued to the operating system, identity spoofing, etc. This, in turn, could lead to massive loss of customer trust and reputational damage alongside the financial costs.
In this article, we delve into the details of SQL injection attacks and how to prevent them.
What are SQL Injection Attacks?
Developed in the 1970s, SQL or Structured Query Language is one of the earliest programming languages used to communicate with or query databases to request information and access data. SQL queries are sent to the database to execute commands such as data retrieval, record removal, database management/ modification, updates, etc.
SQL Injection attacks
SQL Injection attacks occur when the attacker injects malicious code by altering SQL queries to manipulate backend databases. Attackers typically leverage user input sections in applications such as user login, contact/ query forms, comment sections, etc. to inject malicious SQL code to affect the execution of predefined SQL commands. This way, they gain access to information that is not intended to be displayed. These injection attacks are categorized as ‘high impact severity’ by OWASP.
What causes SQLi?
The presence of SQL Injection vulnerabilities in the website/ web application enables attackers to interfere with SQL queries made to the database. These vulnerabilities are often a result of shoddy programming, use of legacy code, etc.
There are 3 broad categories of SQLi:
- In-band SQLi: Attackers launch attacks and gather results using the same communication channels. The simplicity of this type of SQLi makes it the most commonly used attack vector. Error-based SQLi and Union-based SQLi are its sub-variations.
- Inferential or Blind SQLi: Attackers observe responses and behavior of the server to understand database structure. Though slower to execute, these are just as lethal as other types of SQLi attacks. Boolean and Time-based SQLi are its sub-variants.
- Out-of-band SQLi: Attackers leverage this variation of SQLi when the same communication channel cannot be used for launching attacks and gathering information or when the server is too unstable or slow to perform such actions. The presence of certain features in the database servers is a prerequisite for out-of-band SQL injection attacks to be orchestrated.
How do they work?
Attackers typically scan applications for SQL injection vulnerabilities using different methods including crawlers and bots. Once SQLi vulnerabilities are identified, attackers inject arbitrary code into SQL queries to gather the information required.
Attacks try different variations of SQLi using common SQL injection commands to see which of these commands get executed by the database. Based on this, they keep executing SQLi attacks to gain access to the information required. They may stop after gathering what they need or may keep coming back to do their bidding until these vulnerabilities exist.
How are SQL Injections Bot-Driven?
SQL injection attacks today can easily be automated owing to the simplicity of the logic involved. Attackers are leveraging advanced bots to intelligently automate reconnaissance and attacks. Bot armies are readily available as toolkits or as a service for attackers to use.
SQL Injection Attack Prevention
Scanning and Pen-testing to identify SQL Injection vulnerabilities
Intelligent scanning tools as offered by Indusface, effortlessly detect not just SQLi but all known vulnerabilities and when tuned, logical vulnerabilities present in the website/ web application. Through regular scanning, you can detect and secure these vulnerabilities.
Pen-testing by trusted experts like Indusface enable you to understand the exploitability and impact of these vulnerabilities, thus helping you to remediate them.
Managed Web Application Firewall (WAF)
Next-gen, intuitive WAFs like the ones offered by Indusface filter out malicious SQL queries and other threats facing the application. Through a combination of signature, pattern, and behavior analysis, customized whitelisting and blacklisting rules, global threat intelligence, IP reputation history, and other security methodologies, they help in SQL Injection attack prevention with minimum false positives.
Given the bot-driven nature of SQLi attacks, leverage comprehensive security solutions that use intelligent automation.
Though not foolproof solutions, these are best practices in preventing SQL injection attacks.
- Validation of all user inputs to filter out illegitimate and malicious SQL code.
- Use of 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.
From Heartland Payment Systems to Epic Games, several organizations have faced devastating SQL injection attacks over the years. With the advent of technology, these attacks are only becoming more common and lethal, thus, strengthening the case for protecting websites and applications against SQLi.
*** This is a Security Bloggers Network syndicated blog from Indusface authored by Ritika Singh. Read the original post at: https://www.indusface.com/blog/how-to-prevent-bot-driven-sql-injection-attacks/