CVE-2021-1645 in Windows
Summary
by MITRE • 01/13/2021
Windows Docker Information Disclosure Vulnerability
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 05/04/2025
The Windows Docker Information Disclosure Vulnerability identified as CVE-2021-1645 represents a critical security flaw in Microsoft Windows operating systems that affects Docker container implementations. This vulnerability allows attackers to potentially access sensitive information about Docker containers and their underlying host system, creating a significant risk for organizations relying on containerized environments. The issue stems from improper handling of container metadata and system information within the Windows Docker runtime components, specifically impacting how container processes interact with host system resources and expose internal state information.
The technical root cause of this vulnerability lies in the insufficient validation and access control mechanisms within the Windows Docker implementation. When Docker containers are created and managed on Windows systems, the underlying runtime components fail to properly isolate container metadata from unauthorized access by malicious actors. This flaw manifests when container processes attempt to query or access system information that should remain restricted to authorized administrative functions. The vulnerability is classified under CWE-200, which addresses information exposure issues, and specifically relates to improper information flow control within containerized environments. Attackers can exploit this weakness to extract sensitive data including container configuration details, host system identifiers, and potentially credential information that could be used for further exploitation.
The operational impact of CVE-2021-1645 extends beyond simple information disclosure, as it creates a foundation for more sophisticated attacks within containerized environments. Organizations running Windows Docker containers are at risk of having their container orchestration systems compromised, potentially allowing attackers to map container networks, identify running services, and understand the host system architecture. This information disclosure can facilitate privilege escalation attacks and provide attackers with insights into the container environment that would normally be restricted. The vulnerability particularly affects systems where Docker containers are used for application deployment and where security isolation between containers and the host system is paramount for maintaining operational security.
Mitigation strategies for this vulnerability require immediate attention from system administrators and security teams. Microsoft has released security updates addressing this issue through regular Windows updates, and organizations should prioritize applying these patches to all affected systems. Additionally, implementing network segmentation and access controls around Docker hosts can help limit the potential impact of information disclosure. Security monitoring should be enhanced to detect unusual container metadata access patterns and unauthorized queries to system information. Organizations should also consider implementing container runtime security solutions that provide additional isolation layers and monitor for suspicious activities. The ATT&CK framework categorizes this vulnerability under technique T1082, which involves discovering information about the system, and T1566, which covers credential access through social engineering, making it particularly dangerous in environments where attackers can leverage information disclosure for further exploitation. Regular security assessments and container security audits should be conducted to ensure proper isolation and access controls are maintained across all Docker implementations.