CVE-2019-3683 in Openstack Cloud
Summary
by MITRE
The keystone-json-assignment package in SUSE Openstack Cloud 8 before commit d7888c75505465490250c00cc0ef4bb1af662f9f every user listed in the /etc/keystone/user-project-map.json was assigned full "member" role access to every project. This allowed these users to access, modify, create and delete arbitrary resources, contrary to expectations.
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Analysis
by VulDB Data Team • 03/24/2024
The vulnerability described in CVE-2019-3683 represents a critical access control flaw within the SUSE OpenStack Cloud 8 environment, specifically affecting the keystone-json-assignment package. This issue stems from improper role assignment mechanisms that fail to enforce proper access controls based on user identity and project boundaries. The flaw exists in the configuration management system that governs how user permissions are mapped to project resources within the OpenStack infrastructure, creating a scenario where unauthorized access can occur across all projects within the cloud environment.
The technical root cause of this vulnerability lies in the implementation of the user-project mapping system where the keystone-json-assignment package fails to properly validate or restrict user access based on their intended project scope. Instead of implementing proper role-based access control mechanisms that would limit users to specific project boundaries, the system assigns full member roles to all users listed in the user-project-map.json file. This configuration error creates a privilege escalation scenario where any user in the mapping file gains unrestricted access to every project in the cloud infrastructure, effectively bypassing the intended multi-tenancy and security boundaries that separate different project environments.
The operational impact of this vulnerability is severe and far-reaching within the OpenStack cloud environment. An attacker who can access or manipulate the user-project-map.json file can immediately gain complete administrative privileges across all projects, enabling them to access, modify, create, and delete arbitrary resources without restriction. This level of access violates fundamental security principles and can lead to complete compromise of the cloud infrastructure, data loss, unauthorized resource consumption, and potential lateral movement to other systems within the cloud environment. The vulnerability essentially eliminates the security boundaries that should exist between different projects and users, creating a single point of failure that can be exploited to gain access to sensitive data and critical infrastructure components.
This vulnerability aligns with CWE-284 Access Control Issues, specifically addressing improper access control mechanisms that allow unauthorized users to gain elevated privileges. The flaw also relates to ATT&CK technique T1078 Valid Accounts, where adversaries leverage legitimate credentials to gain access to systems and maintain persistence. The improper role assignment creates a scenario where users can escalate their privileges beyond their intended scope, violating the principle of least privilege that is fundamental to secure system design. Organizations implementing this vulnerable configuration face significant risk of data breaches, regulatory compliance violations, and operational disruption due to the unauthorized access capabilities this vulnerability provides.
The recommended mitigations for this vulnerability include immediate patching of the keystone-json-assignment package to the fixed version that properly implements role-based access control. System administrators should also conduct comprehensive reviews of all user-project mappings to ensure that access controls are properly configured according to the principle of least privilege. Additionally, implementing proper monitoring and alerting mechanisms around user access patterns and role assignments can help detect anomalous behavior that might indicate exploitation attempts. Organizations should also consider implementing additional security controls such as multi-factor authentication and regular access control audits to prevent unauthorized modifications to critical configuration files. The fix should ensure that user role assignments are properly validated against project boundaries and that access controls are enforced consistently across all projects within the OpenStack environment.