CVE-2010-2473 in Drupal
Summary
by MITRE
Drupal 6.x before 6.16 and 5.x before version 5.22 does not properly block users under certain circumstances. A user with an open session that was blocked could maintain their session on the Drupal site despite being blocked.
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Analysis
by VulDB Data Team • 11/08/2019
The vulnerability described in CVE-2010-2473 represents a critical session management flaw in the Drupal content management system that persisted across multiple versions prior to the release of Drupal 6.16 and 5.22. This issue stems from inadequate session validation mechanisms that fail to properly terminate active user sessions when administrators block accounts. The flaw exists in the core authentication and authorization subsystem of Drupal, specifically in how the system handles session validation during user account status changes. When an administrator blocks a user account, the system should immediately invalidate any existing sessions associated with that account to prevent unauthorized access. However, the vulnerability allows blocked users to continue operating within the system under their existing session until the session expires naturally, creating a window of opportunity for continued unauthorized access.
The technical nature of this vulnerability aligns with CWE-613, which describes inadequate session management where the system fails to properly handle session invalidation upon account changes. This weakness specifically manifests in the authentication flow where session tokens remain valid even after account blocking operations have been performed. The flaw operates at the application layer within the user management and session handling components of Drupal's architecture. Attackers could exploit this by maintaining access to a system while an administrator is performing account management tasks, potentially allowing them to continue executing privileged actions or access restricted content. The vulnerability demonstrates a failure in the principle of least privilege and proper access control enforcement, as the system does not adequately validate user credentials against current account status during active session operations.
The operational impact of this vulnerability extends beyond simple unauthorized access, potentially enabling attackers to perform administrative actions, modify content, or access sensitive data while maintaining their blocked session. This creates a significant risk for organizations relying on Drupal for content management, particularly those with multiple administrators or users with elevated privileges. The vulnerability is particularly dangerous because it can be exploited without requiring additional authentication credentials, as the attacker simply needs to maintain their existing session. This allows for prolonged unauthorized access that may go undetected for extended periods, potentially leading to data compromise, content tampering, or other malicious activities. The attack surface is broad since any user who has been blocked but maintains an active session can continue to operate within the system, making this vulnerability particularly concerning for organizations with high-security requirements.
Organizations should immediately update to Drupal versions 6.16 or 5.22 and later to address this vulnerability, as these releases include proper session invalidation mechanisms that resolve the flaw. The mitigation strategy should also include monitoring for unauthorized account blocking operations and implementing additional access controls such as session timeout configurations and regular security audits. Security professionals should consider implementing network-level controls to detect unusual activity patterns and establish proper incident response procedures for account blocking scenarios. The vulnerability also highlights the importance of proper session management practices and regular security testing of authentication mechanisms. Organizations should review their current session handling configurations and implement additional logging to track account status changes and session activity. This vulnerability serves as a reminder of the critical importance of maintaining up-to-date software and implementing proper access control mechanisms to prevent session hijacking and unauthorized access scenarios that could compromise system integrity and confidentiality.