When one researcher poked at Microsoft’s Entra ID, he found a trapdoor that could have let attackers become anyone in almost any tenant—yes, even global admins. Imagine waking up to find new “you” accounts created overnight, policies flipped, and mailboxes, SharePoint sites, and Azure resources all wide open. That’s why this matters: identity is the new network perimeter, and when identity breaks, everything behind it is at risk.
The short version: legacy pieces (an internal “actor token” system and the retiring Azure AD Graph API) didn’t play nicely together. Combined, they could bypass normal guardrails like Conditional Access and logs, enabling silent cross-tenant impersonation. The good news—Microsoft moved fast with a global fix and added extra protections. But the lesson is bigger than one patch: if you’re still hanging onto old APIs, stale service principals, or permissive app consents, you’re betting your uptime on yesterday’s rules.
What to do now: audit and kill legacy Graph dependencies, rotate secrets and certificates, prune app consents to least privilege, and enable alerting for high-privilege role changes. Enforce MFA everywhere (including admins), move to workload identity federation where possible, lock down cross-tenant access, and review sign-in logs for odd service-to-service activity. Identity debt compounds—pay it down before it pays you a visit.
Follow me for practical identity hardening tips and fast-moving Microsoft security updates.
Source: https://arstechnica.com/security/2025/09/microsofts-entra-id-vulnerabilities-could-have-been-catastrophic/
Comments
Post a Comment