2020

sconwar – sensecon 2020

Much like other events in 2020, our annual internal hackathon took a remote format this year, sporting over 120 hackers from across the globe. We had many challenges available during the conference which included a password cracking challenge, a discord bot challenge and a programming challenge. This post will talk about the programming challenge called sconwar. You can get the source code for it here. incubation Admittedly I was really nervous about the idea for a hacker hackathon in general, but we can only become better hackers by understanding technologies better, more specifically, understanding them by using them. I often hear people say they want to get into programming, for which there are many options, but more often that not the drive ends with “well, what do I code?”.

DualSense Reverse Engineering

Ciao belli! On the 19th of November 2020, SONY finally released the new PlayStation 5 in the UK. A few days earlier in the US, Japan, and Canada. Of course, Play Station 5 came together with a new Wireless Controller, this time named DualSense. I wanted to see if I could continue my PlayStation controller adventures on this new device, following on my previous work. A few SONY installations available in London for the release of the PlayStation 5. DualSense Wireless Controller The DualSense Wireless Controller presents new features such as:

sensecon 2020 ex post facto

When we finally decided on a date, sensecon 2020 was little over a month away. Unlike our public client events, internally sensecon is a three day conference filled with trainings, a hackathon and a ton of fun. Traditionally we would have had the hackathon in person, but this year our only option was to do it remotely. Overall we had a blast, both in the preparation phase but also during the conference. It was the largest one we had to date, consisting of over 120 Orange Cyberdefense hackers from 8 countries around the globe! This blog post will be a reflection on these three days filled with incredibly exciting hacks, talking about how we got there, how it went and what we had learned along the way. All while I recover from a little sleep deprivation.

Szensecon Discord Bot

We have written a lot about SenseCon by now, but there is one more thing we can talk about! In this post I want to detail the Discord bot and associated challenges that we built. We were going to use Discord as our main communication channel and wanted a way to ensure that it was only accessible to Orange Cyberdefense hackers in an automated way. This was a good opportunity to look into writing a Discord bot. If you are looking for the source code, you can find it here.

thumbscr-ews – a python EWS tool

Something I have found myself doing more and more often is using Exchange Web Services (EWS) to bypass 2FA. I do this so that I could look through mail for accounts I have compromised. The 2FA bypass is due to a common misconfiguration which can leave EWS unprotected, and has been known about for ages, mostly from the Black Hills post in 2016. However, most of the tooling appears to be written in PowerShell, and being the lazy person I am I prefer not to start up a Windows VM when I want to see if I can access a persons email. Hence I started just using a small script around the amazing exchangelib where I would just retrieve the top 10 emails using the example provided in the help documentation. I was doing this often enough that I decided to make a more useful tool.

More On Foreign Hashes

This is an update on this previous post on foreign NT hashes where I got things a little wrong by believing the source encoding matters for an NT hash. It doesn’t really, let me show you why. I spent a bit of time exploring further, in particular, I took it down to a test case. Jameel gave me his name as a password in Arabic: Included as a picture because WordPress is messing with my UTF8. “echo d8acd985d98ad9842031|xxd -ps -r” can give it to you straight That’s Jameel1 in Arabic. It’s encoded in UTF8 in most places, whose bytes are:

Pass-the-hash WiFi

Thanks to a tweet Dominic responded to, I saw someone mention Passing-the-hash when I think they actually meant relay. The terminology can be confusing for sure, however, it made me realise that I had never Passed-the-hash with a Wi-Fi network. So having learnt my lesson from previous projects I first made sure this was possible for NT -> MSCHAP by looking at the RFC. 8.1. GenerateNTResponse() GenerateNTResponse( IN 16-octet AuthenticatorChallenge, IN 16-octet PeerChallenge, IN 0-to-256-char UserName, IN 0-to-256-unicode-char Password, OUT 24-octet Response ) { 8-octet Challenge 16-octet PasswordHash ChallengeHash( PeerChallenge, AuthenticatorChallenge, UserName, giving Challenge) NtPasswordHash( Password, giving PasswordHash ) ChallengeResponse( Challenge, PasswordHash, giving Response ) } Looks like you can! As you can see in the above, the ChallengeResponse is created using the NT hash and not the password. I then checked wpa_supplicant to see if this was not a feature already, and it turns out it is! Looking at the wpa_supplicant configuration file it says:

Let me store that for you

A while ago Jonas Lykkegaard disclosed a zeroday that could be used to create files in the SYSTEM folder. CVE-2020-16885 got assigned for this vulnerability, and was since patched with KB4580346. This vulnerability was very convenient for Dynamic-link library (DLL) side-loading, which I will show in this blog post. Below you can find his original Twitter message. Unprivileged users are not allowed to create files in system32 folder- on hyper-v hosts they finally realised that unprivileged lives matters too as anyone can now create files there , with creater as owner, just open like this: pic.twitter.com/Pd6nnqhcKZ

building a hipster-aware pi home server

The end of the year is getting closer, fast, so I figured it was a perfect time to talk about my side project from last year. In this post I want to walk you through setting up a Raspberry Pi as a home server with all of your services running in docker containers with valid Let’s Encrypt certificates without exposing the Pi to the Internet. We will be setting up a myriad of services such as Pihole, SmokePing and Grafana as well as WireGuard for remote access, so buckle up!

DirectAccess and Kerberos Resource-based Constrained Delegation

Background Are you tired of working from home due to COVID? While this is quite a unique situation we find ourselves in, it also provides some fresh opportunities. Lately we have assessed several environments that was meant to provide a secure way for working from home. For one specific engagement, a client delivered one of their laptops that was domain joined. The laptop was accompanied with credentials of a low privilege domain user. The secure connection to their office was provided using DirectAccess.