Microsoft recently released a security advisory regarding an actively exploited critical remote code execution vulnerability in Microsoft Entra ID that is caused by the deserialization of untrusted data. The vulnerability is allowing unauthenticated attackers to execute malicious code over a network.

Through this blog, we will understand what the critical vulnerability in Microsoft Entra ID is about, the threat it poses, and what organizations can do to defend against it.

About the vulnerabilities

The vulnerability is a remote code execution flaw within Microsoft Entra ID, Microsoft’s cloud-based identity and access management service, an important identity-service component.

Microsoft has not disclosed how the vulnerability is exploited, when the exploitation began, or the identity of the threat actor responsible. However, Microsoft has confirmed that it is being exploited in the wild.

The threat posed by the vulnerability

An attacker can exploit the vulnerability to:

• Execute malicious code remotely
• Cause a compromise of Entra ID identity infrastructure
• Disrupt authentication and access-control services
• Orchestrate a follow-on attack against cloud resources and applications

Official security guidance

In its advisory, Microsoft has stated that the vulnerability is already patched and that no customer action is needed since it is a cloud service. However, organizations can continue to use their existing identity-security monitoring and investigation capabilities.

SharkStriker’s recommendations

• Validate that Microsoft Entra ID is being monitored through the organization’s SIEM/XDR platform.
• Review Entra ID audit and sign-in telemetry for suspicious activity.
• Investigate anomalous activity involving privileged accounts and administrative operations.
• Review identity-related alerts corresponding to the period before Microsoft completed its mitigation.
• Maintain monitoring for unusual authentication and access behaviour.
• Ensure appropriate identity-security controls remain enabled as part of the organization’s broader defense-in-depth strategy.
• Do not attempt to apply an endpoint or server patch for this CVE, as Microsoft has stated that the vulnerability was mitigated within the cloud service.

Note: These activities are defense-in-depth recommendations and should not be interpreted as Microsoft-mandated remediation steps for CVE-2026-69836.

SharkStriker’s action

• Vulnerability intelligence validation completed using the Microsoft Security Response Center advisory.
• CVE severity and technical classification reviewed.
• Exploitation status reviewed and identified as exploited in the wild, based on Microsoft’s disclosure.
• Customer impact assessment initiated.
• Detection engineering team notified to review Microsoft Entra ID monitoring coverage.
• Threat hunting recommended for suspicious identity, authentication, and administrative activity where relevant telemetry is available.