The Register: One token to pwn them all: Entra ID bug could have granted access to every tenant

Sep 19, 2025

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Source URL: https://www.theregister.com/2025/09/19/microsoft_entra_id_bug/
Source: The Register
Title: One token to pwn them all: Entra ID bug could have granted access to every tenant

Feedly Summary: Until Microsoft lobbed it into a virtual volcano
A security researcher claims to have found a flaw that could have handed him the keys to almost every Entra ID tenant worldwide.…

AI Summary and Description: Yes

Summary: The text highlights a significant security vulnerability discovered in Microsoft Entra ID, which could potentially compromise the integrity of numerous Entra ID tenants. This finding is particularly relevant to security professionals who are concerned about identity management systems and the potential risks of centralized identity solutions.

Detailed Description:

– A security researcher has identified a vulnerability in Microsoft Entra ID, a key identity management service.
– This flaw reportedly has the potential to grant unauthorized access to almost every Entra ID tenant globally, implying a critical risk associated with identity theft and access management.
– With the increasing reliance on cloud identity platforms, this discovery underscores the importance of robust security measures and continuous monitoring to prevent such vulnerabilities from being exploited.
– Professionals in cloud security, AI, and infrastructure security should take note of this incident as it highlights the challenges associated with safeguarding identity systems, particularly in the context of multi-tenant environments.

Key Insights:

– The discovery of such a wide-reaching vulnerability raises questions about the effectiveness of existing security controls in cloud identity management.
– Organizations utilizing Microsoft Entra ID should conduct immediate reviews of their security postures and implement necessary mitigations.
– This incident serves as a reminder for the necessity of a proactive security stance, including regular vulnerability assessments and adherence to best practices in identity and access management.

Overall, this situation emphasizes the critical importance of vigilance in managing security risks related to identity systems in cloud and infrastructure environments.

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