Security researchers have recently identified a critical vulnerability within Microsoft Entra ID, formerly known as Azure Active Directory, that enables attackers to escalate their privileges to Global Administrator status. This flaw poses a significant threat to organizations relying on Microsoft's cloud-based identity and access management services, potentially allowing unauthorized users to gain comprehensive control over enterprise environments.
The discovered vulnerability exploits weaknesses in the role-based access control (RBAC) system of Microsoft Entra ID. Specifically, it allows attackers to manipulate authentication mechanisms and escalate their privileges within the directory service. By targeting the identity and access management (IAM) infrastructure, unauthorized users can potentially obtain Global Administrator privileges—the highest level of access within an Entra ID tenant.
This privilege escalation technique involves exploiting inconsistencies in how the system validates user permissions during privilege elevation requests. Attackers can craft malicious requests targeting the Microsoft Graph API infrastructure, focusing on endpoints responsible for managing user roles and permissions. This method enables them to bypass traditional security controls and gain unauthorized access to administrative functions typically reserved for legitimate Global Administrators.
Organizations utilizing Microsoft Entra ID for single sign-on (SSO), multi-factor authentication (MFA), and conditional access policies are particularly vulnerable. A successful privilege escalation attack could grant attackers comprehensive control over user accounts, security policies, and sensitive organizational data stored within the Microsoft 365 ecosystem. This level of access could enable threat actors to establish persistent backdoors and maintain long-term unauthorized access to corporate resources.
Another notable vulnerability involves the abuse of Intune permissions for lateral movement and privilege escalation within Entra ID native environments. Mandiant's Red Team demonstrated how attackers could exploit the ReadWrite.All permission granted to Entra ID service principals to move laterally and elevate privileges, even in environments following Microsoft's recommended Enterprise Access model and Tiered security architecture.
Additionally, Secureworks' Counter Threat Unit discovered a flaw in Microsoft Entra ID access reviews that allowed any multi-tenant service principal registered under a victim's tenant to modify access reviews through a vulnerable API, despite lacking necessary permissions. This vulnerability could impair an organization's ability to oversee access to other services that the threat actor wanted to hide.
Source: gbhackers.com Microsoft Entra ID Flaw Enables Privilege Escalation to Global Admin
Understanding the Vulnerability
The discovered vulnerability exploits weaknesses in the role-based access control (RBAC) system of Microsoft Entra ID. Specifically, it allows attackers to manipulate authentication mechanisms and escalate their privileges within the directory service. By targeting the identity and access management (IAM) infrastructure, unauthorized users can potentially obtain Global Administrator privileges—the highest level of access within an Entra ID tenant.This privilege escalation technique involves exploiting inconsistencies in how the system validates user permissions during privilege elevation requests. Attackers can craft malicious requests targeting the Microsoft Graph API infrastructure, focusing on endpoints responsible for managing user roles and permissions. This method enables them to bypass traditional security controls and gain unauthorized access to administrative functions typically reserved for legitimate Global Administrators.
Technical Exploitation Methods
The attack vector centers on manipulating Azure Active Directory Graph API calls. By exploiting these calls, attackers can request elevated permissions that should normally require proper authentication and authorization workflows. This technique allows threat actors to circumvent security boundaries protecting sensitive administrative functions.Organizations utilizing Microsoft Entra ID for single sign-on (SSO), multi-factor authentication (MFA), and conditional access policies are particularly vulnerable. A successful privilege escalation attack could grant attackers comprehensive control over user accounts, security policies, and sensitive organizational data stored within the Microsoft 365 ecosystem. This level of access could enable threat actors to establish persistent backdoors and maintain long-term unauthorized access to corporate resources.
Broader Implications and Related Vulnerabilities
This vulnerability is not an isolated incident. Similar flaws have been identified in Microsoft Entra ID, highlighting systemic issues within the platform's security architecture. For instance, the "nOAuth" vulnerability discovered by Semperis allows attackers to perform full account takeovers with minimal effort by exploiting cross-tenant authentication flaws in Entra ID integrations. This attack can bypass advanced security measures such as MFA, conditional access policies, and zero-trust architectures, affecting approximately 10% of the estimated 150,000 SaaS applications globally.Another notable vulnerability involves the abuse of Intune permissions for lateral movement and privilege escalation within Entra ID native environments. Mandiant's Red Team demonstrated how attackers could exploit the ReadWrite.All permission granted to Entra ID service principals to move laterally and elevate privileges, even in environments following Microsoft's recommended Enterprise Access model and Tiered security architecture.
Additionally, Secureworks' Counter Threat Unit discovered a flaw in Microsoft Entra ID access reviews that allowed any multi-tenant service principal registered under a victim's tenant to modify access reviews through a vulnerable API, despite lacking necessary permissions. This vulnerability could impair an organization's ability to oversee access to other services that the threat actor wanted to hide.
Recommendations for Organizations
In light of these vulnerabilities, organizations should take immediate action to mitigate potential risks:- Enhanced Monitoring: Implement robust audit logging mechanisms to detect unauthorized attempts to access administrative functions.
- Review Identity Governance Frameworks: Conduct comprehensive reviews of existing Global Administrator assignments to ensure proper access controls are in place.
- Strengthen Zero-Trust Architectures: Reinforce zero-trust principles by verifying all requests for elevated privileges and implementing additional verification steps for sensitive operations.
- Apply Security Updates: Stay informed about security updates from Microsoft and apply patches promptly to address known vulnerabilities.
Source: gbhackers.com Microsoft Entra ID Flaw Enables Privilege Escalation to Global Admin
