Blog

Bypassing BitLocker Without a Screwdriver: bitpixie and What You Can Do About It

BitLocker bitpixie attack – TPM-only mode, pre-boot authentication, PCR validation

BitLocker is always a topic in Windows client pentests. For full-disk encryption not to be easily bypassed, BitLocker must be configured securely.

There is in fact a vulnerability that can be used to bypass BitLocker without special hardware – and in principle anyone can exploit it. This post covers the bitpixie attack, why BitLocker’s default mode is vulnerable, and what you can do about it.

Dump Hashes in Windows 11 24H2

lsass.exe hash dump Windows 11 24H2 – extract password hashes, tool adaptation

In this blog post, I describe how I managed to read password hashes from the lsass.exe process memory in Windows 11 24H2. Since this version was still very new at the time of writing this post, some of the issues are due to a lack of tool support and should be resolved in the future. However, this post may also help in adapting the tools for later Windows versions.

Kerberos: How the Authentication Protocol Works

Kerberos protocol – short explanation of Active Directory authentication

Kerberos works similarly to a passport: A passport authority issues the passport after the person has identified themselves. With this passport, they can then go to the border and prove their identity.

Active Directory Tiering: Terminal Servers and Helpdesk

Active Directory Tiering – terminal servers Tier 2, helpdesk group misconfiguration

In this blog post, I will briefly address two often overlooked vulnerabilities and misconfigurations in the Active Directory Tiering model. Specifically, I will focus on the mishandling of terminal servers and the helpdesk user group.

UAC Bypass

User Account Control (UAC) – what is UAC, how to bypass, countermeasure Always Notify

What do we see in the photo? The settings for User Account Control (UAC). But what exactly is that and how can it be bypassed?

BloodHound Introduction for Admins

BloodHound introduction – visualize Active Directory attack paths for admins

BloodHound is a tool developed by penetration testers and red teamers to better identify and visualize attack paths in Active Directory. However, that doesn’t mean it can’t also be used effectively by admins or the blue team.

Exploit CheckPoint vulnerability with one simple command

CVE-2024-24919 CheckPoint VPN Gateway – exploit and extractable information

This week, a vulnerability in the CheckPoint VPN Gateway (CVE-2024-24919) was disclosed. Unfortunately, CheckPoint has provided us with very little information about the impact of this vulnerability. I want to change that! I will show how the vulnerability can be exploited and what information an attacker can extract.

Active Directory Password Policy

Active Directory password policy – NIST vs Microsoft, VidraSec recommendation and Group Policy settings

Unfortunately, setting a good password policy for Active Directory is difficult. This is also because there are several best practices that sometimes contradict each other. In this post, I will try to address the various best practices and give my own recommendation.

Improving the Performance of Linux Guests in Hyper-V

Hyper-V Linux guest performance – improve UI responsiveness, comparable to VMware Workstation

Despite Hyper-V’s impressive performance, its GUI can feel sluggish compared to direct interaction on your host. Finding a solution to this was challenging, as resources were scarce. This post outlines how to configure Hyper-V and Linux virtual machines for a more responsive UI, achieving a performance level comparable to VMware Workstation.

Securing BitLocker: Initial Setup and Defending Against Attacks

BitLocker setup and hardening – full disk encryption, attacks, pre-boot authentication

Firstly, what exactly is BitLocker? BitLocker is Microsoft’s full disk encryption solution. While there are alternative solutions from other companies, my experience shows that BitLocker is the preferred choice for most organizations today. The reasons are straightforward: it’s included at no additional cost and integrates seamlessly with Active Directory and EntraID.

This article will guide you through setting up BitLocker and also go into some of the potential attacks against BitLocker, offering insights into its security features.