Formatted SQL queries can be difficult to maintain, debug and can increase the risk of SQL injection when concatenating untrusted values into the query. However, this rule doesn’t detect SQL injections (unlike rule {rule:csharpsquid:S3649}), the goal is only to highlight complex/formatted queries.

## Ask Yourself Whether

- Some parts of the query come from untrusted values (like user inputs).
- The query is repeated/duplicated in other parts of the code.
- The application must support different types of relational databases.

There is a risk if you answered yes to any of those questions.

## Recommended Secure Coding Practices

- Use parameterized queries, prepared statements, or stored procedures and bind variables to SQL query parameters.
- Consider using ORM frameworks if there is a need to have an abstract layer to access data.

## Sensitive Code Example

    public void Foo(DbContext context, string query, string param)
    {
        string sensitiveQuery = string.Concat(query, param);
        context.Database.ExecuteSqlCommand(sensitiveQuery); // Sensitive
        context.Query<User>().FromSql(sensitiveQuery); // Sensitive

        context.Database.ExecuteSqlCommand($"SELECT * FROM mytable WHERE mycol={value}", param); // Sensitive, the FormattableString is evaluated and converted to RawSqlString
        string query = $"SELECT * FROM mytable WHERE mycol={param}";
        context.Database.ExecuteSqlCommand(query); // Sensitive, the FormattableString has already been evaluated, it won't be converted to a parametrized query.
    }

    public void Bar(SqlConnection connection, string param)
    {
        SqlCommand command;
        string sensitiveQuery = string.Format("INSERT INTO Users (name) VALUES (\"{0}\")", param);
        command = new SqlCommand(sensitiveQuery); // Sensitive

        command.CommandText = sensitiveQuery; // Sensitive

        SqlDataAdapter adapter;
        adapter = new SqlDataAdapter(sensitiveQuery, connection); // Sensitive
    }

## Compliant Solution

    public void Foo(DbContext context, string query, string param)
    {
        context.Database.ExecuteSqlCommand("SELECT * FROM mytable WHERE mycol=@p0", param); // Compliant, it's a parametrized safe query
    }

## See

- OWASP - Top 10 2021 Category A3 - Injection
- OWASP - Top 10 2017 Category A1 - Injection
- CWE - CWE-20 - Improper Input Validation
- CWE - CWE-89 - Improper Neutralization of Special Elements used in an SQL Command
- Derived from FindSecBugs rules Potential SQL/JPQL Injection (JPA), Potential SQL/JDOQL Injection (JDO), Potential SQL/HQL Injection (Hibernate)