Drupal Fixes Highly Critical SQL Injection Flaw

An anonymous reader writes Drupal has patched a critical SQL injection vulnerability in version 7.x of the content management system that can allow arbitrary code execution. The flaw lies in an API that is specifically designed to help prevent against SQL injection attacks. "Drupal 7 includes a database abstraction API to ensure that queries executed against the database are sanitized to prevent SQL injection attacks," the Drupal advisory says. "A vulnerability in this API allows an attacker to send specially crafted requests resulting in arbitrary SQL execution. Depending on the content of the requests this can lead to privilege escalation, arbitrary PHP execution, or other attacks."

Comments

It's not that hard to do it right

[Art3x]

I understand database abstration layers that let you write:

db_query('select * from table where id = 3')

instead of:

mysql_query('select * from table where id = 3')
or
pgsql_query('select * from table where id = 3')

But I'm not sure I understand why you would want even more abstraction that lets you write:

db_select('*').from('table').where({ id: 3 })

---

Sealing against SQL injection isn't that hard. Don't ever write:

select * from table where id = $id

If you see a dollar sign in an SQL string, it should catch your eye. Instead use parametric queries whenever you can:

select * from table where id = ? or
select * from table where id = $1 or
select * from table where id = :id or
whatever your programming language's syntax is.

Maybe variables in queries are unavoidable, if you have some kind of query building code:

if ($x) {
    $table = 'x';
} else {
    $table = 'y';
}

$q = db_prepare("select * from $table where id = ?");

Does anyone have a better way to build up queries?