CVE-2004-0041 in mod_auth_shadow
Summary
by MITRE
The mod_auth_shadow module 1.4 and earlier does not properly enforce the expiration of a user account and password, which could allow remote authenticated users to bypass intended access restrictions.
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Analysis
by VulDB Data Team • 04/23/2019
The mod_auth_shadow module represents a critical authentication vulnerability within Apache web server environments that affects versions 1.4 and earlier. This flaw resides in the module's implementation of user account and password expiration mechanisms, fundamentally undermining the security controls designed to enforce time-based access restrictions. The vulnerability stems from insufficient validation processes that fail to properly enforce account and password expiration policies, creating a persistent security weakness that can be exploited by authenticated attackers.
The technical flaw manifests in the module's inability to properly validate account expiration timestamps and password change requirements during authentication processes. When users attempt to authenticate, the module fails to verify whether their accounts have expired or if their passwords have exceeded the designated validity period. This failure occurs at the authentication validation layer where the module should enforce security policies but instead permits access regardless of expiration status. The vulnerability specifically impacts the module's handling of expiration-related metadata within the authentication flow, creating a bypass mechanism that allows continued access beyond intended policy enforcement periods.
From an operational impact perspective, this vulnerability enables remote authenticated users to maintain access to systems and resources long after their accounts should have been disabled or their passwords changed. Attackers can exploit this weakness to extend their access window indefinitely, potentially allowing for prolonged unauthorized access to sensitive resources. The vulnerability particularly affects environments where account expiration policies are critical for security posture management, such as government systems, financial institutions, or any organization relying on time-based access controls. This weakness essentially nullifies the intended security benefits of account expiration policies and password rotation requirements.
The security implications extend beyond simple access bypass to encompass potential privilege escalation and persistent access threats. An attacker who has already gained authentication credentials can leverage this vulnerability to maintain access beyond the normal expiration periods, effectively circumventing account management controls. This vulnerability aligns with CWE-284 access control weaknesses and can be mapped to ATT&CK techniques related to privilege escalation and persistence. Organizations implementing this module face significant risk of unauthorized access and potential data breaches when accounts are not properly managed according to established security policies.
Mitigation strategies should prioritize immediate patching of the mod_auth_shadow module to versions that properly enforce account and password expiration policies. System administrators must ensure that all affected Apache installations are updated with patched versions that correctly validate expiration timestamps and enforce security policies. Additionally, organizations should implement comprehensive monitoring of authentication events to detect potential exploitation attempts and establish automated account management processes that enforce expiration policies independently of the vulnerable module. Regular security assessments should verify that authentication modules properly enforce all intended access control mechanisms, with particular attention to account expiration and password policy enforcement.