Because the DBI methods have no way of knowing the diffrence between what you should and shouldn't do (much like open), there is no way for it to dissallow multiple statements in one prepare. On that note, if $baz = "'a'; DROP TABLE blah" is acceptable SQL to the server, it is allowed by prepare.

And, here is a bit of a fix, look at the following : 
## Badd
my $sth = $dbh->prepare('SELECT * FROM foo WHERE bar = ?');
$sth->execute($baz)

## Good
my $sth = $dbh->prepare("SELECT * FROM foo WHERE bar = '?'");
$sth->execute($baz)

[download]
The extra quotes would prevent the baz from getting out unless something was passed which was like $baz = "foo'; DROP TABLE blah; SELECT * FROM foo WHERE a = 'B"

In short, there is not definite fix, which goes back to using regexes to validate user entries before touching them to your database/system.
OH, a sarcasm detector, that’s really useful

In reply to Re: DBI Parameter Security by MZSanford
in thread DBI Parameter Security by pileswasp

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