Have you heard about passkeys and AAGuids?

With the availability of passkeys the FIDO2 standards become more accessible in the form of password managers, web-browsers and (mobile) operating systems — without the need for dedicated hardware such as FIDO2 keys. Microsoft is currently in the process of developing support for passkeys and shipping the public preview in Q1 2024: While this is a very welcome addition to make passwordless authentication easily accessible without dedicated hardware such as FIDO2 security keys this also introduces new risks, especially for high value accounts — But why’s that?...

December 1, 2023 · 5 min · 987 words · Nicola Suter

Have you heard of workload identity access token replay?

Microsoft recently made the Microsoft Graph Activity Logs available as part of the Microsoft Entra ID diagnostic settings. This means we can use the MicrosoftGraphActivityLogs Table to enrich custom detections and analytic rules. Within this post I want to elaborate closer on an attack scenario for workload identities that leverage workload identity federation and don’t have any persistent credentials or long lived secrets. But one type of credential artefacts is still theft-able — the short lived access tokens....

November 8, 2023 · 6 min · 1108 words · Nicola Suter

Microsoft Entra Connect Sync Hardening

Microsoft Entra Connect Sync (aka Azure AD Connect) allows establishing hybrid identity scenarios by interconnecting on-premises Active Directory and Entra ID (aka Azure AD) and leveraging synchronisation features in both directions. As you might already know, this brings potential for abuse of the assigned permissions to the involved service accounts and permissions of this service. On the internet are already some posts with subset of this information but I wanted to provide an actionable post with individual measures to implement....

September 24, 2023 · 5 min · 1060 words · Nicola Suter

Why you should use Entra Workload Identity Federation

Microsoft Entra Workload Identity Federation is a hidden gem when dealing with app registrations and service principals because it will significantly improve the security posture of your workload identities. While I already blogged about the more technical and implementation specific details in my GitHub Actions with Entra Workload Identity Federation post, I want to highlight the benefits and scenarios where you can use Workload Identity Federation to access Entra ID protected resources....

September 7, 2023 · 5 min · 921 words · Nicola Suter

Provoking Defender for Identity suspicious certificate usage alerts

Microsoft Defender for Identity (MDI) has announced a new capability back in February to detect suspicious certificate usage for Kerberos authentication. It is already well-known, that Active Directory Certificate Services (ADCS) is a lucrative target for adversaries to achieve persistence in Active Directory as ADCS can be easily misconfigured resulting in an easy way to exploit those misconfigurations. In this post I want to show you how easy those misconfigurations can be abused and how and when such an attempt is detected by Microsoft Defender for Identity new detection capabilities for suspicious certificate usage....

April 11, 2023 · 8 min · 1547 words · Nicola Suter