Category: Technical Reference

Detecting Password Spraying with Security Event Auditing

This article was originally posted on the Trimarc Content Hub on February 10, 2017. A common method attackers leverage as well as many penetration testers and Red Teamers is called “password spraying”. Password spraying is interesting because it’s automated password guessing. This automated password guessing against all users typically avoids account lockout since the logon …

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Entra & Azure Elevated Access Revisited

In early 2020, I published an article on how a Global Administrator could gain control of Azure resources, that no one would know about it, and how this access would persist even after removing them from Global Administrator. From that article: “While Azure leverages Azure Active Directory for some things, Azure AD roles don’t directly …

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Slides Posted for Black Hat USA 2019 Talk: Attacking & Defending the Microsoft Cloud

Attacking and Defending the Microsoft Cloud (Office 365 & Azure AD) Sean Metcalf (Trimarc) & Mark Morowczynski (Principal Program Manager, Microsoft) The allure of the “Cloud” is indisputable. Organizations are moving into the cloud at a rapid pace. Even companies that have said no to the Cloud in the past have started migrating services and …

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AD Reading: Windows Server 2019 Active Directory Features

Windows Server 2019 has several new features, though nothing in this list is related to AD. Note that there is no Windows Server 2019 AD Forest/Domain Functional Level. There are no new features for Active Directory in Windows Server 2019 except one performance update which doesn’t affect most deployments. This update is related to an …

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There’s Something About Service Accounts

Service accounts are that gray area between regular user accounts and admin accounts that are often highly privileged. They are almost always over-privileged due to documented vendor requirements or because of operational challenges (“just make it work”). We can discover service accounts by looking for user accounts with Kerberos Service Principal Names (SPNs) which I …

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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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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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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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