Potential Azure Browser SSO Abuse via MicrosoftAccountTokenProvider.dll Load
This rule detects attempts to abuse Azure Browser Single Sign-On (SSO) by monitoring for the loading of the 'MicrosoftAccountTokenProvider.dll' library. This DLL is involved in requesting OAuth 2.0 refresh tokens for Azure AD-authenticated Windows users on Azure AD-joined machines, enabling SSO in browsers. An attacker could leverage this to authenticate to Azure AD as the compromised user within a browser. The rule filters out legitimate loads by common processes like BackgroundTaskHost.exe, Visual Studio (devenv.exe), Internet Explorer (iexplore.exe), Microsoft Edge (msedge.exe, msedgewebview2.exe), and OneDrive (OneDrive.exe) to reduce false positives.
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