Prevent SQL queries built from strings

Documentos > Code Analysis > Static Analysis Rules > Prevent SQL queries built from strings

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Metadata

ID: csharp-security/sql-injection

Language: C#

Severity: Error

Category: Security

CWE: 89

Description

Never build SQL queries manually. Always have the query built with parameters and then pass the parameters to the prepared statement.

Learn More

CWE-89: Improper Neutralization of Special Elements used in an SQL

Non-Compliant Code Examples

using System.Xml;

class MyClass {
    public static void doQuery(Int32 userId)
    {
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            SqlCommand command = new SqlCommand("SELECT attr FROM table WHERE id=" + userID, connection);
        }
    }
}

using System.Xml;

class MyClass {
    public static void goQuery(Int32 userID)
    {
        String query1 = "SELECT attr FROM table WHERE id=" + userID;
    }
}

Compliant Code Examples

using System.Xml;

class MyClass {
    public static void doQuery(Int32 userID)
    {
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            SqlCommand command = new SqlCommand("SELECT attr FROM table WHERE id=@ID", connection);
            command.Parameters.Add("@ID", SqlDbType.Int);
            command.Parameters["@ID"].Value = userID;
        }
    }
}