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In rare circumstances, prepared statements can harm performance.

SQLite - use sqlite3_prepare() to create a statement object.

Hibernate - use createQuery() with bind variables (called named parameters in Hibernate).

PHP – use PDO with strongly typed parameterized queries (using bindParam()).

NET – use parameterized queries like SqlCommand() or OleDbCommand() with bind variables

Java EE – use PreparedStatement() with bind variables.

In the safe example below, if an attacker were to enter the userID of tom' or '1'='1, the parameterized query would not be vulnerable and would instead look for a username which literally matched the entire string tom' or '1'='1. Prepared statements ensure that an attacker is not able to change the intent of a query, even if SQL commands are inserted by an attacker.

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This coding style allows the database to distinguish between code and data, regardless of what user input is supplied. Parameterized queries force the developer to first define all the SQL code, and then pass in each parameter to the query later. They are simple to write, and easier to understand than dynamic queries.

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The use of prepared statements with variable binding (aka parameterized queries) is how all developers should first be taught how to write database queries. Primary Defenses ¶ Defense Option 1: Prepared Statements (with Parameterized Queries) ¶ String query = "SELECT account_balance FROM user_data WHERE user_name = " + request. Unfortunately, this method for accessing databases is all too common. The unvalidated "customerName" parameter that is simply appended to the query allows an attacker to inject any SQL code they want. The following (Java) example is UNSAFE, and would allow an attacker to inject code into the query that would be executed by the database. SQL injection flaws typically look like this:

Also: Performing Allow-list Input Validation as a Secondary Defense.

Option 4: Escaping All User Supplied Input.

Option 2: Use of Properly Constructed Stored Procedures.

Option 1: Use of Prepared Statements (with Parameterized Queries).

There are other types of databases, like XML databases, which can have similar problems (e.g., XPath and XQuery injection) and these techniques can be used to protect them as well. These techniques can be used with practically any kind of programming language with any type of database.

This article provides a set of simple techniques for preventing SQL Injection vulnerabilities by avoiding these two problems. Developers need to either: a) stop writing dynamic queries with string concatenation and/or b) prevent user supplied input which contains malicious SQL from affecting the logic of the executed query.

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SQL Injection flaws are introduced when software developers create dynamic database queries constructed with string concatenation which includes user supplied input. the attractiveness of the target (i.e., the database typically contains all the interesting/critical data for your application).the significant prevalence of SQL Injection vulnerabilities, and.SQL Injection attacks are unfortunately very common, and this is due to two factors: This article is focused on providing clear, simple, actionable guidance for preventing SQL Injection flaws in your applications. SQL Injection Prevention Cheat Sheet ¶ Introduction ¶ Insecure Direct Object Reference Preventionĭefense Option 1: Prepared Statements (with Parameterized Queries)ĭefense Option 3: Allow-list Input Validationĭefense Option 4: Escaping All User-Supplied InputĮscaping Wildcard characters in Like Clauses