Entra ID B2B Guest Governance & Periodic Access Reviews
Preventing external vendor sprawl and orphaned guest accounts across SharePoint, Teams, and corporate applications.
The Hidden Risk of Orphaned B2B Collaborators
Organizations frequently invite third-party contractors, auditors, and joint-venture partners into Microsoft Teams channels and SharePoint libraries. When contracts terminate, these guest identities often remain active in the tenant indefinitely, creating an unmonitored attack vector.
Implementing Automated Access Reviews
Entra ID Identity Governance allows security teams to configure automated quarterly Access Reviews. Resource owners and group managers receive automated prompts requiring them to certify whether each guest still requires operational access.
Restricting Guest Permissions in Entra ID Defaults
Configure tenant-wide collaboration settings to prevent guest users from browsing other users and groups in the tenant directory. Restrict invitations to designated member roles and mandate that all guest accounts undergo MFA enforcement upon external sign-in.
Related Articles & Advisories
Microsoft 365 Security Baseline: Essential Defensive Hardening Before Audits
A technical walkthrough of default misconfigurations in Microsoft 365 and Entra ID, and the practical controls needed to prevent business email compromise and identity takeover.
Architecting Zero-Trust Conditional Access in Entra ID for Modern Workforces
A deep dive into constructing modular, non-conflicting Conditional Access policies that enforce least-privilege context without locking out legitimate personnel.
Defeating Adversary-in-the-Middle (AiTM) Phishing & Session Token Theft
How modern reverse proxy toolkits steal active browser session cookies and bypass standard SMS/TOTP MFA, and the specific controls needed to prevent token replay.