Windows 11 Privilege Escalation via UAC Bypass (GUI based)

Introduction

Ok these are a really simple UAC bypass from a userland GUI perspective. This is about increasing process integrity levels – it’s not about performing LPE from low integrity to high/SYSTEM with no interaction. These clearly work in older version of Windows as well but since Windows 11 will be the current version in the near future I thought it was fun to re-visit these!

And just to be clear, a medium integrity process as an administrator user will have the following privileges:

What we are talking about here is to move to a high integrity process without knowing credentials or having the secure desktop launch. Read more “Windows 11 Privilege Escalation via UAC Bypass (GUI based)” →

Defense

Razer Privilege Escalation Vulnerability

“And I looked and behold a pale horse: and his name that sat on him was Death, and Hell followed with him.”

Firstly, Kudos to @j0nh4t for finding this!

I woke up this morning to see twitter fun with a LPE discovered in the Razer driver installation. Basically, when you plug a Razer mouse into a Windows machine, it will download (via windows update) and execute a process as system which has user interaction. This interface includes an install path selector, with this a right click + SHIFT (LULZ) on whitespace will allow you to launch a command prompt/PowerShell window (as SYSTEM).

Guides

Hacking Windows Server 2022

WIndows Server 2022 is RTM! I love new operating systems, but also with the new, what is old? There will be loads of new blogs and articles on new features of Server 2022 however I wanted to see what mischief we can have with it! So I’ve decided to start looking at common vectors and exploits (from the fun to the serious) so that we can see how much of the world has changed (or not!)

So let’s take a look. The first thing I did was to offline replace stickykeys with cmd.exe – yes this method still works. But as lots of people will realise, you neeed physical access to the disk (well you don’t if you have access to someone’s vcenter you don’t!) but also the reg key methods also work! We can still backdoor RDP – here’s a script to disable NLA, Enable RDP, configure the firewall rules and set the registry keys to backdoor the system (clearly for lab use only!)

https://github.com/mr-r3b00t/RDP_Backdoor

Defense

Windows Remote Management 101

Windows Remote Management is easy if you are using a domain joined machine and have a CA. But what if you are off the domain and you want to connect to WINRM that has an HTTPS listener? (by default WINRM uses HTTP on TCP 5985, you can clearly chop out the TLS related configs in the example scripts and they will work for plain old WINRM)

This is useful from a sysadmin and penetration testing/red team perspective. Now obviously you could export the certificates and import them into your store, however that’s more work. So, let’s look at how we ignore revocation, CA name and Computer Name checks.

WinRM via HTTPS (self-signed)

Defense

Penetration Testing

Overview

Penetration testing is the activity of conducting security testing with the aim of identifying and exploiting vulnerabilities to identify strengths and weaknesses. I include strengths because I believe it’s important for security testing to promote both positive and negative findings. I also think that there is a huge mis conception with what penetration is, what it helps with and how to best get value from a penetration test.

My definition isn’t too far from the NCSC one: https://www.ncsc.gov.uk/information/check-penetration-testing

A penetration test is a security assurance activity, but it’s one of many activities that I recommend people conduct. This is however largely only adopted by the few, for many a penetration test is a compliance tick box, either from a regulatory or contractual requirement.

When looking at a system a penetration test is not usually the most efficient starting point, especially if it’s from a black box perspective. Read more “Penetration Testing” →

Guides

What do you need to be Cyber Leader?

Introduction

What does it take to be a cyber leader? How do we address a broad challenge we have in today’s business world?

There are a huge number of organisations whereby the leadership do not have domain expertise in cyber and related disciplines. There are decision makers who are having to best guess. On the other end of the spectrum, we have thousands and thousands of people trying to “break into cyber” yet they face largely insane entry requirements with the forementioned adding things to junior and entry level role which include:

Must have a CISSP (CISSP requires 5 years’ experience and is an Information Security certificate that is very broad and not very deep, it also covers a range of areas that in my opinion aren’t even required for many cyber security capabilities inside organisations)
Must have a Certified Ethical Hacker (this exam includes remember historic malware dates, is that really what we need from our leaders?)
Must have a very large level of experience of be from an existing cyber role

Leadership

There’s never any time – A mRr3b00t Adventure

Introduction

I’ve been working with technology and its security for a while, I have travelled to different parts of the world, I’ve worked with major organisations, and I’ve worked with a whole range of organisations both from strategic advisory and at the coal face perspective. Now over the last twenty years I thought about how much has changed… and honestly, I don’t think much has.

Technology innovation, miniaturisation and adoption rates are through the roof, but I still see massively similar patterns. I’m not going to try and quote statistics, but I think it’s a fair to say the threat landscape has changed somewhat (for the worse!)

Back in the 2000s era we had networks running Windows 2000 and Windows Server 2000/2003, we had clients with open services which could largely be accessed from anywhere on the network. We had host-based firewalls from third party vendors, but these were rarely implemented, MSBlaster and Windows XP changed this dynamic somewhat, to say things haven’t improved on one front would be a lie, however the level of crime and access to technology globally has changed massively. Read more “There’s never any time – A mRr3b00t Adventure” →

Defense

Audit NTDS.DIT using DSINTERNALS

Ok this assumes you know how to get the NTDS.DIT and SYSTEM registry hive out from a domain controller, if you don’t go looking, we might have blogged a few ways to do that! Now then, firstly, let’s Install DSInternals. From PowerShell 5 onwards you can simply run:

Install-Module -Name DSInternals -Force

You will likely need to set your execution policy:

Set-ExecutionPolicy -ExecutionPolicy Unrestricted

Now to dump the hashes we use: Read more “Audit NTDS.DIT using DSINTERNALS” →

Defense

Dumping Credentails with MIMIKATZ and Passing the Hash (PTH)

I kid you not, I forget the commands, so I thought, hey let’s write a small blog post on credential dumping and pass the hash.

To achieve this we need: Debug privileges on a single machine or we need access to a disk that does not have full disk encryption. We also need the password to be re-used.

Mimikatz

Ok for this demo I’m going to run with the out of the box release for Mimikatz on a domain joined windows PC with Defender disabled.

To gain system we launch mimikatz from an admin shell and run:

privilege::debug

token::elevate

Now we are SYSTEM we access a range of high privilege level areas. Read more “Dumping Credentails with MIMIKATZ and Passing the Hash (PTH)” →

Defense

Hacking Guide – AESREPRoast and Kerberoasting

Kerberos Pre-Authentication Hash Retrieval and Cracking

We can enumerate active directory to find accounts that do not require pre-authentication. There’s a simple way of doing this using Rubeus:

.\Rubeus.exe asreproast /format:hashcat

We can see there is a vulnerable account that has Kerberos Pre-Authentication disabled.

This hash can be loaded into hashcat and possibly cracked (the hash in the screenshot is weak on purpose) Read more “Hacking Guide – AESREPRoast and Kerberoasting” →