INSIDER THREAT SECURITY BLOG

The Techniques Attackers Use and Best Practices for Defending Your Organization Introduction An attacker who gets into your network is seldom content with their initial foothold. To achieve their ultimate objective, whether that’s stealing sensitive information or planting malware, they need to leverage the account they have compromised to move laterally through your environment and escalate their privileges until they gain access to more data or resources. In other words, the accoun…

Active Directory persistence through userAccountControl manipulation I’ve been doing some research on group Managed Service Accounts (gMSAs) recently and reading the MS-SAMR protocol specification for some information. I happened to stumble across some interesting information in the userAccountControl section which made us drop what we were doing to test it: Figure 1 – Part of the userAccountControl section of the MS-SAMR specification Effectively, when the UF_SERVER_TRUST_…

In this blog post, we are taking a deeper dive into Covenant. Covenant is one of the latest and greatest Command and Control (C2) Post Exploitation Frameworks which I covered in In my previous blog post. In that post, we discussed Covenant on a high level but now let’s go through the process of configuring and using Covenant to execute payloads on compromised hosts. NOTE: This post demonstrates the capabilities of Covenant in Mid-September 2019. Getting Setup and Starting Covenant T…

What Organizations Can Do to Stop a DCShadow Attack Recently, I came across a post outlining how companies CANNOT effectively defend against a DCShadow attack but instead need to take a reactive approach to identify when it may have occurred by monitoring their environment, and rolling back any unwanted changes once they were identified. Unfortunately, reacting to an incident could mean the damage is already done and a malicious actor has run off with the ‘keys to the kingdom’. The best co…

Today, I came across an interesting article (since posting, the original post has been taken offline) where the author described how an attacker could manipulate the permissions on extended attributes to create persistence once they have compromised an Active Directory domain.  Read the article for a great breakdown of the attack, but here’s a quick summary. Step 1 – Domain Compromise An attacker compromised Domain Admin privileges within Active Directory and wants to make sure the…

Lateral movement techniques like Pass-the-Hash, Pass-the-Ticket, and Overpass-the-Hash provide attackers with ways to take stolen or compromised credentials and spread out across a network to achieve privilege escalation.  I recently found myself testing some Active Directory attacks from a Kali Linux host, and needed a way to use compromised credentials from this Linux system on my Windows boxes.  Luckily, this is something supported by Mimikatz and surprisingly easy to perform.&nb…

Abusing RBCD and MachineAccountQuota Delegation is an area that is confusing and complicated for most Active Directory administrators. Unconstrained delegation, constrained delegation, and even resource-based constrained delegation all play a role in not only your Active Directory infrastructure, but also its security posture. For example, unconstrained delegation is very insecure, and can be abused relatively easily. If you’re unfamiliar with the different types of delegation and how they…

In this post we will discuss the concept of Honey Pots, and how StealthDEFEND utilizes Honey Tokens in its threat detection to provide an additional line of defense against attackers. Introduction to Honey Pots Wikipedia defines “Honey Pots” as a computer security mechanism set to detect, deflect, or, in some manner, counteract attempts at unauthorized use of information systems. Honey Pots are not a new concept in the realm of Information Security. Implementations of Honeypots …

A lot of my posts have covered Mimikatz and how it can be used to explore Active Directory and Windows security to learn how various attacks work.  Recently, the author of Mimikatz released a new feature which exposes a new attack surface that could be used to create persistence within AD.  This feature uses a subauthentication package to manipulate the Active Directory login process and escalate user privileges based on arbitrary conditions.  Basically, an attacker with ac…

In this blog post, we’ll be talking about the DCSync attack and how we can use StealthDEFEND to detect and respond to this type of attack. DCSync was the topic of previous STEALTHbits Blog post, so we’ll start this post with a review of DCSync and then cover what we can do about this attack with StealthDEFEND. What is DCSync? DCSync is a late-stage kill chain attack that allows an attacker to simulate the behavior of Domain Controller (DC) in order to retrieve passwo…