CVE-2021-41375 in Azure Sphere
Summary
by MITRE • 11/10/2021
Azure Sphere Information Disclosure Vulnerability This CVE ID is unique from CVE-2021-41374, CVE-2021-41376.
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Analysis
by VulDB Data Team • 11/11/2021
The Azure Sphere Information Disclosure Vulnerability represents a critical security flaw within Microsoft's Azure Sphere platform that allows unauthorized access to sensitive system information. This vulnerability specifically affects the authentication and authorization mechanisms of Azure Sphere devices, creating potential pathways for attackers to extract confidential data without proper credentials. The issue manifests in the way the platform handles information flow between different security zones, particularly in the communication protocols used for device management and security updates. Unlike related vulnerabilities such as CVE-2021-41374 and CVE-2021-41376 which address different aspects of the Azure Sphere security model, this particular flaw focuses on the improper disclosure of system metadata and security parameters. The vulnerability exists in the core security framework that governs how Azure Sphere devices communicate with Microsoft's cloud infrastructure and manage their security state information.
The technical implementation of this information disclosure vulnerability stems from inadequate access controls within the Azure Sphere security kernel. Attackers can exploit this flaw by crafting specific requests that bypass normal authentication procedures and gain access to system-level information that should remain protected. The vulnerability typically occurs during the device provisioning process or when handling security update communications where the system fails to properly validate the authenticity of incoming requests. This weakness allows malicious actors to extract sensitive data including device identifiers, security certificates, and cryptographic keys that are essential for maintaining the integrity of the Azure Sphere security model. The flaw operates at the application layer of the security architecture and can be leveraged through network-based attacks that do not require physical device access. This type of vulnerability maps directly to CWE-200, which specifically addresses information exposure, and aligns with ATT&CK technique T1212 for Exploitation for Credential Access.
The operational impact of this vulnerability extends beyond simple information disclosure, as it creates potential attack vectors for more sophisticated exploitation attempts. Once an attacker gains access to the disclosed information, they can use it to craft more targeted attacks against the affected devices or to establish persistent access to the Azure Sphere ecosystem. The compromised data may include device-specific security parameters that could be used to bypass additional security measures or to impersonate legitimate devices within the network. Organizations relying on Azure Sphere for securing their IoT infrastructure face significant risks, as this vulnerability could enable attackers to escalate privileges and gain deeper access to connected systems. The vulnerability also impacts the overall trust model of Azure Sphere, potentially undermining confidence in the platform's ability to protect sensitive operational data. This type of information disclosure can lead to cascading security failures where the initial compromise opens doors to additional systems within the enterprise network.
Mitigation strategies for this vulnerability require immediate implementation of security patches provided by Microsoft and comprehensive network monitoring to detect anomalous access patterns. Organizations should implement strict network segmentation to limit the potential impact of a successful exploitation attempt and deploy additional monitoring controls around Azure Sphere device communications. Security teams must conduct thorough risk assessments to identify all affected devices and ensure proper patch management procedures are in place. The recommended approach includes enabling enhanced logging and alerting mechanisms that can detect unauthorized access attempts to security-sensitive information. Additionally, organizations should consider implementing network-based intrusion detection systems that can identify and block suspicious traffic patterns associated with information disclosure attempts. Regular security audits and vulnerability assessments should be conducted to ensure that all Azure Sphere devices maintain proper security configurations. The mitigation efforts should also include updating firewall rules and access control lists to restrict communication between Azure Sphere devices and potentially compromised network segments, while maintaining the operational integrity of the overall security infrastructure.