Hello @Shim Kwan , Azure AD B2C is a Customer Identity Management System optimized to store millions of user accounts and handle billions of authentication requests per day. Thanks to being built on the same technology that powers Azure AD it shares common security features such as Identity Protection and Conditional Access, MFA, the Zero Trust Security Model, and more.
Please take a look to the following and subsequent security guidelines for more information for How to Improve the Security of a B2C tenant:
- Monitor Azure AD B2C with Azure Monitor
- Configure security analytics for Azure Active Directory B2C data with Microsoft Sentinel
- Configure Azure Web Application Firewall with Azure Active Directory B2C
- Configure Microsoft Dynamics 365 Fraud Protection with Azure Active Directory B2C
- Investigate risk with Identity Protection in Azure AD B2C
- Add Conditional Access to user flows in Azure Active Directory B2C
- Mitigate credential attacks in Azure AD B2C with smart lockout
- Securing phone-based multi-factor authentication (MFA)
Currently, Microsoft Defender for Cloud and MS Purview Suite are not available for Azure AD B2C..
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