CVE-2002-0170 in Zope
Summary
by MITRE
Zope 2.2.0 through 2.5.1 does not properly verify the access for objects with proxy roles, which could allow some users to access documents in violation of the intended configuration.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 09/22/2025
The vulnerability described in CVE-2002-0170 affects Zope content management systems version 2.2.0 through 2.5.1, specifically targeting the access control mechanisms that govern object permissions within the system. This issue represents a critical flaw in the authorization framework that could potentially allow unauthorized users to bypass intended access restrictions and gain access to protected documents and resources. The vulnerability stems from improper verification of access controls for objects that utilize proxy roles, which are mechanisms designed to provide temporary or conditional access permissions to users. Proxy roles in Zope are intended to allow specific users or groups to access objects under certain conditions while maintaining overall system security boundaries.
The technical flaw manifests in the way Zope handles access control verification when proxy roles are involved in the permission checking process. When objects are configured with proxy roles, the system should rigorously validate whether the requesting user possesses the appropriate permissions to access those objects. However, in the affected versions, this verification process fails to properly enforce the intended access controls, creating a pathway for privilege escalation. The vulnerability specifically impacts the authorization subsystem where proxy roles are processed, allowing users with insufficient privileges to potentially access documents that should be restricted to specific user groups or roles. This represents a fundamental breakdown in the principle of least privilege that is central to secure system design and aligns with CWE-284, which addresses improper access control mechanisms.
The operational impact of this vulnerability extends beyond simple unauthorized access to encompass potential data breaches and system compromise. An attacker exploiting this vulnerability could gain access to sensitive documents, configuration files, or system resources that are normally protected by access control lists. The implications are particularly severe in enterprise environments where Zope systems might host confidential business information, user data, or proprietary content. The vulnerability affects the core security model of Zope, potentially allowing attackers to escalate their privileges and access resources that should be restricted to administrators or specific user roles. This type of access control bypass can lead to complete system compromise when combined with other vulnerabilities or when the affected system hosts critical business data. The issue is particularly concerning given that it affects multiple versions of Zope 2.x, indicating a widespread problem that would require extensive patching across affected installations.
Organizations utilizing Zope systems should implement immediate mitigations to address this vulnerability, including applying the relevant security patches provided by the Zope community and implementing additional access controls at the network level. System administrators should conduct thorough audits of access control configurations to identify and remediate any potential unauthorized access paths. The recommended approach includes reviewing proxy role configurations, implementing additional logging and monitoring of access attempts, and ensuring that proper access control testing is performed after any configuration changes. This vulnerability demonstrates the critical importance of proper access control implementation and serves as a reminder of the need for regular security assessments of content management systems. The issue also highlights the necessity of following security best practices such as those outlined in the OWASP Top Ten and other industry standards for secure application development and deployment. Organizations should also consider implementing network segmentation and additional security controls to limit the potential impact of such vulnerabilities. The vulnerability's classification under CWE-284 emphasizes the need for robust access control mechanisms and proper authorization checking throughout the application lifecycle.