SQL Injection
SQL Injection involves entering SQL code into web forms, eg. login fields, or into the browser address field, to access and manipulate the database behind the site, system or application.
When you enter text in the Username and Password fields of a login screen, the data you input is typically inserted into an SQL command. This command checks the data you've entered against the relevant table in the database. If your input matches table/row data, you're granted access (in the case of a login screen). If not, you're knocked back out.
SQL Injection
SQL Injection involves entering SQL code into web forms, eg. login fields, or into the browser address field, to access and manipulate the database behind the site, system or application.
When you enter text in the Username and Password fields of a login screen, the data you input is typically inserted into an SQL command. This command checks the data you've entered against the relevant table in the database. If your input matches table/row data, you're granted access (in the case of a login screen). If not, you're knocked back out.
The authorization SQL query that is run by the server, the command which must be satisfied to allow access, will be something along the lines of:
SELECT * FROM users WHERE username = ‘USRTEXT '
AND password = ‘PASSTEXT’
…where USRTEXT and PASSTEXT are what the user enters in the login fields of the web form.
So entering `OR 1=1 — as your username, could result in the following actually being run:
SELECT * FROM users WHERE username = ‘' OR 1=1 — 'AND password = '’
Two things you need to know about this:
['] closes the [username] text field.
'
' is the SQL convention for Commenting code, and everything after Comment is ignored. So the actual routine now becomes:
SELECT * FROM users WHERE username = '' OR 1=1
1 is always equal to 1, last time I checked. So the authorization routine is now validated, and we are ushered in the front door to wreck havoc.
Let's hope you got the gist of that, and move briskly on.
Brilliant! I'm gonna go hack me a Bank!
Slow down, cowboy. This half-cooked method won't beat the systems they have in place up at Citibank, evidently.
