CVE-2007-0405 in Django
Summary
by MITRE
The LazyUser class in the AuthenticationMiddleware for Django 0.95 does not properly cache the user name across requests, which allows remote authenticated users to gain the privileges of a different user.
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Analysis
by VulDB Data Team • 08/17/2018
The vulnerability described in CVE-2007-0405 represents a critical authentication bypass flaw within the Django web framework version 0.95. This issue resides in the AuthenticationMiddleware component and specifically affects the LazyUser class implementation that handles user authentication state management. The flaw fundamentally undermines the security model of the application by creating a scenario where authenticated users can potentially impersonate other users within the same session. This type of vulnerability falls under the category of privilege escalation and session management failures that can severely compromise the integrity of user access controls.
The technical root cause of this vulnerability stems from improper caching mechanisms within the LazyUser class implementation. When a user authenticates to a Django application, the system should maintain a consistent and secure user context across multiple requests. However, in version 0.95, the authentication middleware fails to properly maintain the user name in cache between requests, creating a condition where subsequent requests may reference an outdated or incorrect user identity. This caching failure occurs at the middleware level where user authentication state should be consistently preserved and validated. The vulnerability specifically manifests when the system attempts to retrieve user information from cache, but the cached data becomes stale or corrupted, allowing unauthorized privilege elevation.
The operational impact of this vulnerability extends beyond simple authentication bypass to encompass potential data breaches and unauthorized access to sensitive user information. An authenticated attacker who successfully exploits this vulnerability can effectively impersonate other users within the application, gaining access to their respective accounts, personal data, and associated privileges. This risk is particularly severe in applications where users have varying levels of access rights, as the attacker could potentially escalate privileges to administrative or elevated user roles. The vulnerability affects all authenticated users within the application, making it a systemic threat rather than an isolated incident, and could lead to widespread unauthorized access across the entire user base.
Organizations running Django 0.95 applications should immediately implement mitigations to address this vulnerability, including upgrading to a supported Django version that contains the necessary security patches. The recommended approach involves applying the official security update that corrects the LazyUser class caching implementation and ensures proper user state management across requests. Additionally, implementing proper session management controls and monitoring for unusual authentication patterns can help detect potential exploitation attempts. Security teams should also consider conducting comprehensive audits of their authentication systems and reviewing access controls to ensure that user privileges are properly enforced. This vulnerability demonstrates the critical importance of proper session management and caching mechanisms in web applications, aligning with cybersecurity principles outlined in standards such as CWE-284 for improper access control and CWE-306 for missing authentication. The flaw also relates to ATT&CK techniques involving privilege escalation and credential access, emphasizing the need for robust authentication middleware implementations in web frameworks.