From the MySQL’s C API function mysql_real_escape_string description: If you need to change the character set of the connection, you should use the mysql_set_character_set() function rather than executing a SET NAMES (or SET CHARACTER SET) statement. mysql_set_character_set() works like SET NAMES but also affects the character set used by mysql_real_escape_string(), which SET NAMES does not. … Read more
Stored Procedures and/or prepared statements: https://stackoverflow.com/questions/1973/what-is-the-best-way-to-avoid-sql-injection-attacks Can I protect against SQL Injection by escaping single-quote and surrounding user input with single-quotes? Catching SQL Injection and other Malicious Web Requests With Access DB, you can still do it, but if you’re already worried about SQL Injection, I think you need to get off Access anyway. Here’s … Read more
To avoid injections, use execute with %s in place of each variable, then pass the value via a list or tuple as the second parameter of execute. Here is an example from the documentation: c=db.cursor() max_price=5 c.execute(“””SELECT spam, eggs, sausage FROM breakfast WHERE price < %s”””, (max_price,)) Note that this is using a comma, not … Read more
According to the official documentation: If you need to generate dynamically an SQL query (for instance choosing dynamically a table name) you can use the facilities provided by the psycopg2.sql module. The sql module is new in psycopg2 version 2.7. It has the following syntax: from psycopg2 import sql cur.execute( sql.SQL(“insert into {table} values (%s, … Read more
SQL injection attacks happen when user input is improperly encoded. Typically, the user input is some data the user sends with her query, i.e. values in the $_GET, $_POST, $_COOKIE, $_REQUEST, or $_SERVER arrays. However, user input can also come from a variety of other sources, like sockets, remote websites, files, etc.. Therefore, you should … Read more
Consider two ways of doing the same thing: PreparedStatement stmt = conn.createStatement(“INSERT INTO students VALUES(‘” + user + “‘)”); stmt.execute(); Or PreparedStatement stmt = conn.prepareStatement(“INSERT INTO student VALUES(?)”); stmt.setString(1, user); stmt.execute(); If “user” came from user input and the user input was Robert’); DROP TABLE students; — Then in the first instance, you’d be hosed. … Read more
Placeholders are enough to prevent injections. You might still be open to buffer overflows, but that is a completely different flavor of attack from an SQL injection (the attack vector would not be SQL syntax but binary). Since the parameters passed will all be escaped properly, there isn’t any way for an attacker to pass … Read more
First of all, you should NEVER do SQL command compositions on a client app like this, that’s what SQL Injection is. (Its OK for an admin tool that has no privs of its own, but not for a shared use application). Secondly, yes, a parametrized call to a Stored procedure is both cleaner and safer. … Read more
Well, here’s the article you want. Basically, the way the attack works is by getting addslashes() to put a backslash in the middle of a multibyte character such that the backslash loses its meaning by being part of a valid multibyte sequence. The general caveat from the article: This type of attack is possible with … Read more
Your advice is indeed incorrect. mysql_real_escape_string() will not work for dynamic table names; it is designed to escape string data, delimited by quotes, only. It will not escape the backtick character. It’s a small but crucial distinction. So I could insert a SQL injection in this, I would just have to use a closing backtick. … Read more