Category "security"

HTB: Writeup

Writeup Card

This article is a writeup about a retired HacktheBox machine: Writeup. (Yes the machine name is writeup, searching a writeup for writeup will be a funny thing.). The machine is classed as an easy one. It involves vulnerability in a known CMS as well as "PATH vulnerability" for the privilege escalation.

HTB: Swagshop

Swagshop Card

This article is a writeup about a retired HacktheBox machine: Swagshop This box was suppose to be an easy one. Turns out it wasn't. I struggle a lot in wrong direction and finally found a path to root this magento box.

This article presents the different methods which failed on the box as well as the solution to root it.

Breaking some homemade crypto

I recently did a code review assessment on an application for one of my client. The best part of the application was their own cryptography algorithm.

Moreover, the application was written in PHP and PHP do some strange things with string, characters and XOR operations. It only needed a few lines of python in order to break it.

TL;DR : please do not write your own crypto!

Insomnihack Teaser 2017

This week-end was the insomnihack teaser CTF. I participated with the team The Half Crunchy.

The theme was "RISE OF THE MACHINES" with rogue webserver and flawing cat robot.

We finished 42th with 550 points flagging 5 challenges:

scoreboard

Many thanks to the organisation! It was a really nice CTF.

Thanks to all team members who participated.

Let's encrypt certificate for offline servers with OVH DNS

Let's encrypt provide free and easy SSL certificates. Nevertheless it need to verify that you own the machine. In order to do that we usually use HTTP verification with the .well-known directory.

But sometime our servers are not reachable from the internet. Therefore the HTTP validation is not possible. Hopefully there is another way the acme challenge can be validated: DNS validation.

In this post we will see how we can generate Let's encrypt SSL certificate for offline machine with DNS validation for domains hosts by OVH.