How to defend against SQL injection attacks?

What is SQL injection attack

SQL injection is an attack method that adds sql code to the input parameters and passes it to the sql server for parsing and execution.

How does sql injection occur?

1. Web developers cannot guarantee that all input has been filtered.

2. The attacker uses the input data sent to the sql server to construct executable code.

3. The database does not have corresponding security configuration (set a specific database account for the web application instead of using the root or administrator account. The specific database account gives permissions for some simple operations and recycles some operations like drop) permissions).

sql injection attack defense

1. Use parameterized filtering statements

In order to prevent SQL injection, user input cannot be directly embedded in SQL statements. Instead, user input must be filtered or parameterized. Parameter statements use parameters instead of embedding user input into the statement. In most cases, the SQL statement is correct. User input is then limited to one parameter.

Generally speaking, there are two ways to ensure that an application is not vulnerable to SQL injection attacks. One is to use code review and the other is to enforce the use of parameterized statements. Forcing the use of parameterized statements means that SQL statements embedded in user input will be rejected at runtime. However, there is currently not much support for this feature.

2. Avoid using interpreters, which are used by hackers to execute illegal commands.

3. Prevent SQL injection, but also avoid detailed error messages, because hackers can use these messages. Standard input validation mechanisms are used to verify the length, type, statements and enterprise rules of all input data.

4. Use professional vulnerability scanning tools.

However, preventing SQL injection attacks is not enough. Attackers now automatically search for and attack targets. Its techniques can even be easily applied to vulnerabilities in other web architectures. Enterprises should invest in professional vulnerability scanning tools, such as the famous Accunetix Network Vulnerability Scanner. A perfect vulnerability scanner is different from a network scanner in that it specifically looks for SQL injection vulnerabilities on websites. The latest vulnerability scanners find the latest discovered vulnerabilities.

5. Finally, enterprises perform code security checks at all stages of the web application development process. First, security testing should be implemented before deploying web applications, which is more important and far-reaching than before. Businesses should also test websites after deployment using vulnerability scanning tools and site monitoring tools.

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