Sean Metcalf

I improve security for enterprises around the world working for TrimarcSecurity.com Read the About page (top left) for information about me. :) https://adsecurity.org/?page_id=8

Author's posts

From DNSAdmins to Domain Admin, When DNSAdmins is More than Just DNS Administration

It’s been almost 1.5 years since the Medium post by Shay Ber was published that explained how to execute a DLL as SYSTEM on a Domain Controller provided the account is a member of DNSAdmins. I finally got around to posting here since many I speak with aren’t aware of this issue. Shay describes this …

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Domain Controller Print Server + Unconstrained Kerberos Delegation = Pwned Active Directory Forest

At DerbyCon 8 (2018) over the weekend Will Schroeder (@Harmj0y), Lee Christensen (@Tifkin_), & Matt Nelson (@enigma0x3), spoke about the unintended risks of trusting AD. They cover a number of interesting persistence and privilege escalation methods, though one in particular caught my eye. Overview Lee figured out and presents a scenario where there’s an account …

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Black Hat & DEF CON Presentation Slides Posted

I just uploaded the slides from my Black Hat & DEF CON talks from the past week in Vegas.  They are a bit different with the BH talk more Blue (defensive) and the DC talk mostly Red (Offensive) in focus. Also note that the only real overlap in content is the MFA & password vault …

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NolaCon (2018) Active Directory Security Talk Slides Posted

I recently presented my talk  “Active Directory Security: The Journey” at Nolacon in New Orleans, LA. Slides are now posted here. On Sunday, May 19th, 2018, I spoke at NolaCon at 11am. Here’s the talk description: Active Directory is only the beginning. Attackers have set their sights squarely on Active Directory when targeting a company, though …

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Attacking Read-Only Domain Controllers (RODCs) to Own Active Directory

I have been fascinated with Read-Only Domain Controllers (RODCs) since RODC was released as a new DC promotion option with Windows Server 2008. Microsoft customers wanted a DC that wasn’t really a DC. – something that could be deployed in a location that’s not physically secure and still be able to authenticate users. This post …

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Securing Microsoft Active Directory Federation Server (ADFS)

Many organizations are moving to the cloud and this often requires some level of federation. Federation, put simply, extends authentication from one system (or organization) to another. Gerald Steere (@Darkpawh) and I spoke about cloud security at DEF CON in July 2017. Presentation slides and video are here: “Hacking the Cloud” One of the key …

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Beyond Domain Admins – Domain Controller & AD Administration

Active Directory has several levels of administration beyond the Domain Admins group. In a previous post, I explored: “Securing Domain Controllers to Improve Active Directory Security” which explores ways to better secure Domain Controllers and by extension, Active Directory. For more information on Active Directory specific rights and permission review my post “Scanning for Active …

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AD Reading: Windows Server 2016 Active Directory Features

The following are useful resources for Windows Server 2016 Active Directory Features.   Windows 2016 Features What’s New in Windows 2016 Active Directory Windows Server 2016 AD Functional Level   Privileged Access Management (PAM) Windows 2016 PAM Shadow Security Principals (temporary group membership)   Azure AD Join Windows 2016 Azure AD Join   Microsoft Hello …

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