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

Enriching Microsoft Sentinel tables with eligible Entra directory roles

Microsoft 365 Defender and Sentinel provide an IdentityInfo table that contains various information that is helpful for threat hunting and detections. One key piece are also the assigned Entra directory roles for a specific identity. Unfortunately only permanently assigned permissions are covered and in times of Entra Privileged Identity Management (PIM) we should have standing permissions only for non-privileged roles and break-glass accounts. Within this blog post I want to share a few tips and tricks to answer the following questions with Sentinel and a little bit of scripting and KQL:...

November 17, 2023 · 5 min · 1050 words · Nicola Suter

Maintaining Microsoft Sentinel Analytic Rules in JSON and YAML with GitHub Actions

Microsoft Sentinel Analytic Rules can be shared in both the YAML and ARM format, whereas the ARM format leverages JSON as file type. Within… Microsoft Sentinel Analytic Rules can be shared in both the YAML and ARM format, whereas the ARM format leverages JSON as file type. Within this short post I want to demonstrate an approach that leverages a GitHub Action to automatically build and update the rules in YAML format — so you can just export and update existing rules without any manual conversion effort....

November 13, 2023 · 4 min · 707 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