CVE-2021-22012 in vCenter Server
Summary
by MITRE • 09/24/2021
The vCenter Server contains an information disclosure vulnerability due to an unauthenticated appliance management API. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to gain access to sensitive information.
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Analysis
by VulDB Data Team • 10/02/2021
The vulnerability identified as CVE-2021-22012 represents a critical information disclosure weakness within VMware vCenter Server deployments that directly violates fundamental security principles of access control and data protection. This flaw exists within the appliance management API component of vCenter Server, which operates without proper authentication mechanisms, creating an attack surface that allows unauthorized actors to extract sensitive operational data from the system. The vulnerability specifically affects the management API interface that typically requires administrative credentials and secure authentication protocols, yet in this case operates in an unauthenticated state that compromises the integrity of the entire virtual infrastructure management system.
The technical implementation of this vulnerability stems from improper security controls within the vCenter Server appliance management API, where the system fails to enforce mandatory authentication checks before exposing sensitive operational information. This design flaw allows attackers to connect directly to the management interface through standard network protocols and port 443, which is the default HTTPS port used by vCenter Server for secure communications. The vulnerability essentially creates a backdoor access point that bypasses normal authentication mechanisms, enabling attackers to perform reconnaissance activities and gather critical system information including configuration details, user credentials, and operational parameters that could be used for further exploitation attempts.
From an operational impact perspective, this vulnerability poses significant risks to enterprise virtualization environments that rely on vCenter Server for managing their VMware infrastructure. The information disclosure can provide attackers with detailed insights into the virtual environment structure, including virtual machine configurations, network settings, and administrative access details that would normally be restricted to authorized personnel only. This exposure creates a substantial risk for organizations as it enables attackers to map their target environment more effectively, identify potential attack vectors, and plan subsequent exploitation phases. The vulnerability particularly affects organizations with complex virtual infrastructures where the exposure of management API information could lead to cascading security incidents across multiple virtual machines and network segments.
The exploitation of this vulnerability aligns with several tactics and techniques documented in the MITRE ATT&CK framework, particularly under the information gathering and credential access phases. Attackers can leverage this vulnerability as part of reconnaissance activities to identify system components, gather operational data, and map network topology before launching more sophisticated attacks. The vulnerability also relates to CWE-287 which addresses improper authentication issues in software systems, and CWE-312 which covers exposure of sensitive information through improper data handling. Organizations implementing the affected vCenter Server versions face increased risk of privilege escalation attacks and lateral movement within their virtual environments, as the disclosed information could enable attackers to identify specific system weaknesses and target administrative accounts for compromise.
Effective mitigation strategies for CVE-2021-22012 require immediate implementation of network-level controls to restrict access to the vulnerable management API endpoints, including firewall rules that limit access to port 443 from trusted network segments only. VMware has released patches and updates to address this vulnerability, and organizations should prioritize applying these security updates to ensure proper authentication enforcement within the appliance management API. Network segmentation and monitoring solutions should be deployed to detect and alert on unauthorized access attempts to management interfaces, while regular security audits should verify that authentication mechanisms are properly enforced throughout the vCenter Server deployment. Additionally, organizations should implement comprehensive access control policies that limit administrative privileges and ensure that management interfaces are only accessible from secure, trusted environments that have proper network security controls in place to prevent unauthorized access attempts.