Natas 16 is a more secure version of Natas 9 and 10. In this challenge, the server-side code the challenge author provides us allows a passthru but filters on most characters in bash that would allow us to do much at all. read more

This is a solution guide to the Vortex Level 00 at overthewire. This write-up was created on 09 September 2015. read more

NATAS 15

NATAS 15 demonstrates how confirming the contents of a username can be combined with a SQL Injection vulnerability to enable what’s called a Blind SQL Injection attack. If we click on the View sourcecode link shown in the screenshot above, we can once again view the server-side PHP script that the challenge author made available to us (see below). read more

This is a solution guide to the Narnia0 Level at overthewire. This write-up was created on 19 November 2014.

Challenge Description: Narnia0 is the beginning challenge for pwnable style challenges on overthewire. It requires the attacker to utilize a buffer overflow in order to overwrite a variable named val with the hexidecimal value 0xdeadbeef. When the attack is successful the vulnerable program will execute a system command which produces a shell. This challenge requires the attacker to send hexidecimal values after determining the buffer overflow offset. read more

NATAS 14 presents you with a login form and yet again provides you with a link to view the PHP script that processes form submissions.

This page was specifically crafted for this challenge to let you see the script that runs on the server. Normally, you wouldn’t be able to view PHP on the client unless something was misconfigured or it was intentionally displayed. read more

Step 1: View the source code

The only difference between this level and natas12 is the line where the file is checked for an image signature. If you click “View Source Code” at http://natas13.natas.labs.overthewire.org/index-source.html, you’ll see this function: read more

Step 1: Write the “payload script”

Create a php file to display the natas13 password read more