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” →

Changing a security posture requires changing your own behaviours

I’m sure you will have had a marketing firm or some random sales person on Linkedin tell you that security should be simple and that their product will save you from all the ATPs and nation state hax0rs under the sun. However let’s get real, thats almost certainly not true and also security isnt simple or we’d all be out of jobs and everyon woulndn’t be getting owned all the time.

Getting real

Read more “Changing a security posture requires changing your own behaviours” →

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: Part 2a – Persistence, Privilege Escalation and…

Recap

In Part 1 (Initial Access Defence and Checklist) we looked at ways of hardening your attack surface to defend against initial access. When it comes to ransomware there is a range of elements and variables in the kill chain that need to be successful for the outcomes to be achieved by the criminals. Here we are going to move further into the kill chain to look at further defences. Remember you need to have an “Assume Breach” mindset if you are going to be able to defend against ransomware, that being said, there is a hell of a lot of things you can do for 0 to low investment costs that provide a great ROI. Now some of this is going to be repeated guidance from part 1, that’s ok repetition is good (make sure you are covered from multiple perspectives). Ok let us get to it! Read more “Ransomware Defence: Part 2a – Persistence, Privilege Escalation and Lateral Movement” →

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