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What is SQL Injection and Know the SQLI Attacks, Prevention and Mitigation

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What is SQL Injection?

SQL Injection is a kind of cyber-attack based on targeted databases by submitting malicious SQL code instead of input on web application fields.

This code is created with the purpose of affecting the structure of the database query that the application interacts with the backend database, thus making it vulnerable to hackers who can breach its security, modify data or carry out malicious actions.

Generally, SQL injection is done through login forms, search boxes, or any user-controlled filter fields, in which a web application interacts with a backend database through SQL queries.

Using the unprepared handling of application inputs as their point of entry, the attackers can bypass authentication, extract private information such as usernames and passwords, or worse, gain total control of the whole database server.

Speaking of SQL Injection attacks, these attacks present a huge threat to web applications that use SQL databases for storing and retrieving data; otherwise, a big potential damage may follow.

Types of SQL injection

There are several types of SQL injection attacks, each exploiting different vulnerabilities in web applications and database servers:

1. Classic SQL Injection
This is the most general type of SQL injection vulnerability. Attackers normally embed the malicious SQL code within a few input fields, including login areas or search query boxes, and sometimes in the URL parameters of a web application.

Injected SQL code opens the database to SQL injection, which can be used to tamper with the regular SQL query processed by the database server to steal sensitive data, such as usernames, passwords, or any other private data.

2. Blind SQL Injection
In this SQL injection attack, attackers cannot see direct feedback from the application on whether the injected SQL queries they sent are successful. On the contrary, they exploit methodologies like logical and time-based blind insertion to guess the database parameters remotely.

By getting a response from the application, the attacker can check which expression is true and false which eventually leads to the information extracting or other malicious purposes.

3. Error-based SQL Injection
Error-based SQL injection attacks work by taking advantage of the error messages that the database server sends when it faces malformed SQL queries.

Attackers use SQL injection attacks that involve SQL code copies with the aim of triggering database errors and then dissecting received messages to figure out database schema or content.

This kind of data may assist attackers in improving their assault strategy and identifying individuals that they can proceed to attack.

4. Union-based SQL Injection
Union-based SQL injection attacks use UNION statements in SQL to return the result set of two or more SELECT statements.

Injected by an adversary, a UNION SELECT statement is run by the database server, executing additional queries and returning them together with the original query results.

The hacker is able to snoop on other database tables that might not have been directly accessible through the application.

5. Time-based SQL Injection
Time-based SQL injection attacks expose the database functions that are executed with the help of the database server-specifics, such as the delay feature of the query execution.

Attackers insert SQL code that captures the database server response time when the injected condition is true, they can in this way make a query by the type of information they need from the database.

Time elapsed in receiving different inputs to or from the server is attacked which in turn leads to extracting data or performing other malicious actions.

6. Out-of-Band SQL Injection
Unlike In-Band SQL injections, which use web-based techniques to attack the database servers, Out-of-Band SQL injections leverage the ability of the server to have an external system connection.

Attackers could introduce SQL code that results in off-network requests that, in turn, allow them on the remote systems to communicate with the attacker or carry away the data.

This method is especially effective when the most expeditious communication channel with the compromised system gets disconnected or blocked.

How & Why is an SQL Injection Attack Performed?

SQL injection attacks are achieved by accepting unauthorized SQL code into ordinary SQL statements through the web application and using the data in SQL databases with the intention of updating information without permission.

The vulnerabilities of such platforms could eclipse intruders with unauthorized access of sensitive information and even to the extent of gaining complete control of attacked websites, applications, and database servers.

SQL injection attacks do not only happen in one way. For example, executing commands on the database server, retrieving data based on errors, or manipulating query logic.

To block SQL injection attacks, the secure programming functions to be used should be parameterized queries and stored procedures.

The software and components must be kept in an updated version, the input to be validated as an allow list is suggested, the Principle of Least Privilege needs to be implemented, and the web application firewalls to filter the web request must also be used.

Biggest Example of an SQL Injection Attack

The Equifax data breach that happened in 2017 is one of the most prominent SQL injection attacks. Attackers managed to take advantage of the security flaw in Equifax’s website software, which was Apache Struts, which was not downloaded with the latest security updates.

This opening offered the attackers a chance to insert malevolent SQL commands into Equifax’s database.

Thus, the hackers that were able to use this vulnerability got unauthorized access to about 147 million people’s sensitive personal information such as names, birth dates, addresses, Social Security numbers, and in some cases, even driver’s licenses.

The culprits obtained hundreds of terabytes of information over six weeks and had no idea. The impact of the Equifax breach was extensive, with many individuals experiencing identity theft or financial fraud as a consequence.

In addition to substantial financial and brand damage, Equifax faced multiple lawsuits, investigations by regulatory bodies, and loss of the confidence of customers.

This case shares the lesson of the necessity to have sound security measures to prevent SQL injection attacks, including regularly updated software with the most recent security patches, strategic coding practices, and stricter controls for authorized access to sensitive databases

What is the Impact of a Successful SQL Injection Attack?

The impact of a successful SQL injection attack can be severe and wide-ranging:

Data Breach:
Pirates may use unpermitted methods such as Mechanical Access, Social Engineering, and SQL Injection to breach databases and thereby leak restricted information like personal details, financial data, intellectual property, and others.

Identity Theft:
Stolen personal data, including names, SSNs, and credit card details, may end up being used by identity thieves for fraudulent purposes and causing monetary damages as well as harm to your credit score

Financial Losses:
Cybercrime greatly affects the financial status of organizations as they might suffer a pecuniary loss due to theft of financial data, fraudulent transactions, regulatory penalties as well as legal costs involved in solving the problem.

Reputation Damage:
An SQL injection attack can lead to such a data breach, which can ruin the reputability of an organization and harm clients’ trust in it.

As a result, companies can witness a drop in their sales, attracting unwanted negative coverage and tarnishing reputation in the long run.

Legal Consequences:
Organizations may be on the hook to pay settlements or lose revenue if they get sued by affected individuals or fined by regulators for non-compliance to data protection laws (for example, the GDPR or CCPA). Also, the organizations could be investigated by the regulatory authorities.

Operational Disruption:
In most cases, tampering with a SQL injection involves disruption of normal business operations that necessitates resources such as investigation of the entrance, ameliorating influence, and putting security changes in motion to prevent recurrence.

Loss of Competitive Advantage:
The worst-case scenario would be what happens when confidential information or trade secrets are revealed. It may be that another and more advantageous competitor would emerge after they get access to your privileged intellectual property.

Get know about How to Detect, Prevent and Best Practices to Protect Your Database from SQL Injection

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