Category: redteaming

[Edit 6/14/16] I was mistaken on a few points in the Local Account Management – Restricted Groups section, which I have now corrected. Thanks to @DougSec for the question/catch. Enumerating the membership of the Administrators local group on various computers is something we do on most of our engagements. This post will cover how to do this with Group Policy Object (GPO) correlation and without sending packets to every machine we’re enumerating these memberships for. I touched on this briefly in the Tracking Local Administrators by Group Policy Objects section of my “Local Group Enumeration” post back in March, but with a number of recent bug fixes…

A friend (@piffd0s) recently ran into a specific situation I hadn’t encountered before: the domain controllers and domain admins of the environment he was assessing were extremely locked down, but he was able to determine that a few users had edit rights on a few specific group policy objects (GPOs). After a bit of back and forth, he was able to abuse this to take down his target, and we were able to integrate some new functionality into PowerView that facilitates this process. This post will cover these new features and demonstrate how to enumerate and abuse misconfigured GPOs in case you encounter…

I’ve found that one of the most useful features of PowerView (outside of its user hunting capabilities) is its ability to enumerate local group membership on remote machines. I’ve spoken about this briefly before, and gave some details on its utilization of the ADSI WinNT Provider in the “Pass-the-Hash is Dead: Long Live Pass-the-Hash” post. My colleague @sixdub wrote an excellent post titled “Derivative Local Admin” that shows the power this functionality can give attackers, and fellow ATD member @_wald0 expanded on this with his “Automated Derivative Administrator Search” post. This functionality has been indispensable on both our pentests and longer-term red-team engagements. I wanted…

Following my pattern of weaponizing Sean Metcalf‘s work in PowerView, I’m here with another update. Sean recently released a post titled “Dump Clear-Text Passwords for All Admins in the Domain Using Mimikatz DCSync“. He describes a legacy feature for Active Directory user accounts called ‘reversible encryption’. According to Microsoft, “This policy is required when using Challenge-Handshake Authentication Protocol (CHAP) authentication through remote access or Internet Authentication Services (IAS). It is also required when using Digest Authentication in Internet Information Services (IIS)“. There’s a bit more a detailed explanation of its workings here and here. Sean describes a cool way to set this policy…

One of my favorite presentations at Derbycon V was Sean Metcalf (@pyrotek3)’s talk “Red vs. Blue: Modern Active Directory Attacks & Defense“. In it, Sean had a section focused on “Sneaky AD Persistence Tricks”, meaning methods “by which an attacker could persist administrative access to Active Directory after having Domain Admin level rights for 5 minutes“. I wanted to show how one of the methods covered, the abuse of AdminSDHolder and SDProp, can be facilitated with new PowerView 2.0 functionality. Note: I did not discover this attack method. I also will only give a brief background on the underlying components, as Sean has…

PowerView is a tool that I’ve spoken frequently about on this blog. It debuted as part of the Veil-Framework in March of 2014, and has gone through a huge number of changes over the last year and a half. It is now a part of the PowerTools repository under the PowerShellEmpire GitHub account, and may be integrated soon into the central PowerSploit repository. Today marks probably the biggest change to PowerView and how people use it since its inception. PowerView v2.0 is a major refactor that eliminates some code components, renames others, absorbs some functions into existing ones, and adds a chunk of new functionality. As…