Category Archives: Active Directory

The video of our presentation at Veeam Live is now available

Veeam organized its Veeam Live event on October 20th, 2020. Veeam is defining the future of cloud data solutions and helping today’s businesses securely and reliably protect and easily recover their data. At Veeam Live, they offered data protection management guidance, showed how to up your data protection game and allowed to connect with like-minded […]


Two vulnerabilities in VMware ESXi may lead to virtual Domain Controller compromise (Critical, VMSA-2020-0026, CVE-2020-4004, CVE-2020-4005)

Today, VMware released an update that addresses a use-after-free vulnerability in the XHCI USB controller (CVE-2020-4004) and a VMX elevation-of-privilege vulnerability CVE-2020-4005). Together these two vulnerabilities can be used to compromise virtual Domain Controllers running on ESXi. Note: The vulnerabilities exist in VMware Cloud Foundation, too. The two vulnerabilities were responsibly disclosed to VMware by […]


Kerberos Security Feature Bypass Vulnerability (Important, CVE-2020-17049, CVSSv3 6.6)

Yesterday, for its November 2020 Patch Tuesday, Microsoft released an important security update for Active Directory Domain Services (AD DS).   About the vulnerability A Kerberos Security Feature Bypass vulnerability exists in Microsoft’s implementation of the Kerberos network authentication protocol. This vulnerability is described in detail in CVE-2020-17049. A security feature bypass vulnerability exists in […]


The video of my talk at the European SharePoint Office 365 and Azure Conference is now available

The European SharePoint, Office 365 & Azure Conference (ESPC) is Europe’s leading online community, providing educational resources and encouraging collaboration. Therefore, I was more than happy to announce that I was returning as a speaker for the European SharePoint, Office 365 and Azure Conference (ESPC) 2020. On October 15th, while my pre-recorded presentation was playing, […]


Azure AD Connect version and older versions are no longer supported

As announced as part of the Azure AD Connect Version Release History page and shared here earlier, yesterday marked the end of Azure AD Connect version and older versions of Azure AD Connect. This way, Microsoft starts enforcing its 18-month support policy for Azure AD Connect versions. For Azure AD Connect admins, running an […]


Group Policy Elevation of Privilege Vulnerability (CVE-2020-16939, Important)

On Tuesday October 13th 2020, Microsoft released updates for all supported versions of Windows and Windows Server to address an elevation of privilege vulnerability in Group Policy, marked as important. Its official common vulnerabilities and exposures (CVE) id is CVE-2020-16939. Yesterday, the Zero Day Initiative (ZDI) shared more details and a Proof of Concept (PoC). […]


From the Field: The case of the randomly rebooting Domain Controllers

Troubleshooting stories from the field are the best. That’s why I like writing them down. Although, sometimes they might appear as straight cases of schadenfreude, I feel there are lessons to be learned for anyone, if you’re willing to look closely and listen carefully. Last month, I experienced an issue with all four Domain Controllers […]


Mainstream support for Microsoft Advanced Threat Analytics (ATA) ends in three months

We’ve helped organizations embrace Microsoft’s Advanced Threat Analytics (ATA) solution to protect their Active Directory environments from attacks. On January 12th, 2021, mainstream support for this product ends. ATA version 1.9.3, released on September 14th, 2020 is the final update as part of mainstream support. It’s time to move on to Microsoft Defender for Identity. […]


Active Directory-related sessions at VMware VMworld 2020

VMware’s VMworld 2020 event kicks off in one week. For 2020, VMworld is organized differently to align with the new reality. Instead of multiple VMworld events, one virtual VMworld event is organized. This VMworld 2020  ‘Online Around the Globe’ event is held from September 29th to October 1st, 2020. The big advantage for you, is […]


HOWTO: Attach a previously sync’ed Azure AD Tenant to a new AD Forest

This week, I was contacted by an organization who were in the process of starting anew with Active Directory Domain Services (AD DS). The old Active Directory forest was too … old, basically. It showed signs of problems around attribute integrity, schema extension bloat and delegation defaults from the 00’s. The challenge I assisted with, […]