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” →

Why are ransomware attacks so devastating? – Part 1

Introduction

“Ransomware is a major issue!”

Hang on maybe we need to re-phrase that:

“Weak security postures are a major issue!”

or perhaps.. why not both!

I’ve been working with digital technology management for over 20 years, I started out when I was a kid (literally) fixing people’s PCs in their offices, removing malware, improving configurations, writing batch file menus, and playing games. As time has gone on technology has shrunk and continually become more and more of our everyday lives.

Back in 2003 I responded internally to MSBlaster, an SMB worm that had a devastating effect for the time, by today’s standards it was child play, however I remember saying “it’s a good job it didn’t delete everything whilst it was here.” (Or something very similar. Post NACHI/Blaster my friends and I were talking about how worse it could get. Fast forward in time and it’s much worse. Yet when I look at networks, they don’t look very different to how they did back in the 2000s.

Despite a multi-billion-dollar cyber security industry, it seems daily that organisations are succumbing to “cyber-attacks” which commonly include ransomware. Why are they successful and why are they so impactful? Well, let’s take a look! Read more “Why are ransomware attacks so devastating? – Part 1” →

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

Text Description automatically generated

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” →

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)” →

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” →

PetitPotam

From Zero to DA using ‘PetitPotam’

Introduction

Whilst I was on ‘holiday’ (seriously even when on holiday I almost always must do some work!) a few Windows vulnerabilities were published. Great work by Gilles Lionel, Benjamin Delpy and many many others!

Lab Setup

  • A Domain Controller
  • A Separate ADCS Install with Web Enrolment or two DCs one with ADCS installed.
  • A windows Client Device (non-domain joined)
  • An attacker device (I used Kali)

You do not need any domain credentials to conduct this exploit chain, so from a network adjacent unauthenticated position you can get DA with the right circumstances (default configuration). Read more “From Zero to DA using ‘PetitPotam’” →

Ransomware Realities

Everything is much worse now, or is it? 

”The world is burning, the world is burning but then if you look around, it always has been…” 

Computer systems and security go together much like chalk and cheese! Probably sounds a bit odd but miniaturization, consumerization and mobility have put more technology out in the world than we can really comprehend, yet technology security is still dramatically overlooked by most organizations. 

The insane pace of change, the drive for faster, better, cheaper and the reality that it probably isn’t a stretch to say most people (and organizations) do not really understand what ‘secure’ or ‘hardened’ looks like.

Read more “Ransomware Realities” →

Confessions of a white hat hacker

We move around in many places, we sit in plain sight, you might know we are there, or you might not. We work in the shadows, yet we shine a light. You see we’ve been inside your networks; we’ve sat in your cabs, we’ve worked with your teams. We have read you annual reports and we’ve mapped your company; we do this in a way that often you can’t even see.

Read more “Confessions of a white hat hacker” →

Ransomware Defence Checklist – Part 1 : Initial Access

Defending the Realm

We keep seeing organization get hit, in some kind of a sick way I think me and some of my friends in the industry are bored with the over dramatic responses of “sophisticated” “advanced” and “unpreventable” because most times the kill chains simply are not like this. But still the onslaught keeps coming. Well I know this much, whilst I would love to deploy with the team and harden everyone’s networks that simply isn’t possible. So what we thought we would do is write something to try and spread the knowledge a bit further and hopefully have some positive impact.

Ransomware 101

It’s not just that your data will be encrypted, it will likely be exfiltrated and sold. You will likely have access sold, data sold and be extorted. The Ransomware business model is adapting to defender responses. Even if you can restore from backup they will likely try and attempt to extort. This brings a key point in this equation, the best position is to NOT get pwn3d to start with. Ok that might sound silly to say but when we look at these kill chains you might start to see the world from my perspective a little. Read more “Ransomware Defence Checklist – Part 1 : Initial Access” →

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