23 results for DCSync

Dump Clear-Text Passwords for All Admins in the Domain Using Mimikatz DCSync

The two key goals of any attack is access and persistence. This post covers elements of each. In a post-exploitation scenario where the attacker has compromised the domain or an account with delegated rights, it’s possible to dump the clear-text passwords of admins without being a Domain Admin*. This method requires the Active Directory Domain …

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Mimikatz DCSync Usage, Exploitation, and Detection

Note: I presented on this AD persistence method at DerbyCon (2015). A major feature added to Mimkatz in August 2015 is “DCSync” which effectively “impersonates” a Domain Controller and requests account password data from the targeted Domain Controller. DCSync was written by Benjamin Delpy and Vincent Le Toux. The exploit method prior to DCSync was …

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Active Directory Security Tip #15: Active Directory Domain Root Permissions

This week let’s look at Active Directory domain permissions which are configured on the domain root and apply to the domain. There are many different type of concerning permissions, but let’s look at the most egregious.

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The History of Active Directory Security

During the Summer of 2024, I had a talk at Troopers called “A Decade of Active Directory Attacks:What We’ve Learned & What’s Next” (Slides & Video) where I focused on the key milestones of Active Directory security (history). This article covers my “decade of Active Directory attacks” in some detail which was correlated with public …

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Kerberos Bronze Bit Attack (CVE-2020-17049) Scenarios to Potentially Compromise Active Directory

Introduction & Attack Overview Jake Karnes (@jakekarnes42) with NetSPI published 3 articles (that’s right 3!) describing a new attack against Microsoft’s Kerberos implementation in Active Directory. He posted an Overview article, describing how the attack works, an Attack article on practical exploitation, and if you need further background on Kerberos, a Theory article. This article …

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Mitigating Exchange Permission Paths to Domain Admins in Active Directory

This article is a cross-post from TrimarcSecurity.comOriginal article: https://www.trimarcsecurity.com/single-post/2019/02/12/Mitigating-Exchange-Permission-Paths-to-Domain-Admins-in-Active-Directory The Issue Recently a blog post was published by Dirk-jan Mollema titled “Abusing Exchange: One API call away from Domain Admin ” (https://dirkjanm.io/abusing-exchange-one-api-call-away-from-domain-admin/)which highlighted several issues with Exchange permissions and a chained attack which would likely result in a regular user with a mailbox being able to …

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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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Attack Defense & Detection

This page is meant to be a resource for Detecting & Defending against attacks. I provide references for the attacks and a number of defense & detection techniques. Active Directory & Windows Security ATTACK AD Recon Active Directory Recon Without Admin Rights SPN Scanning – Service Discovery without Network Port Scanning Beyond Domain Admins – …

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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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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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