CVE-2017-12197 in libpam4j
Summary
by MITRE
It was found that libpam4j up to and including 1.8 did not properly validate user accounts when authenticating. A user with a valid password for a disabled account would be able to bypass security restrictions and possibly access sensitive information.
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Analysis
by VulDB Data Team • 12/24/2019
The vulnerability identified as CVE-2017-12197 affects the libpam4j library version 1.8 and earlier, representing a critical authentication flaw that undermines the fundamental security controls of system access management. This issue resides within the Pluggable Authentication Modules framework implementation for java applications, where proper account validation mechanisms fail to function correctly. The flaw specifically impacts how the library handles authentication requests for user accounts that have been disabled within the system, creating a significant security gap that allows unauthorized access through seemingly legitimate authentication attempts.
The technical implementation of this vulnerability stems from inadequate account status verification during the authentication process. When a user attempts to authenticate using valid credentials against a disabled account, the libpam4j library fails to properly check the account's active status before granting access privileges. This failure occurs at the authentication validation layer where the system should verify that the account is not only valid but also active and enabled for access. The lack of proper account state validation creates an authentication bypass condition that allows malicious actors or authorized users with knowledge of disabled accounts to circumvent security controls that should prevent access to sensitive resources.
The operational impact of CVE-2017-12197 extends beyond simple unauthorized access to encompass potential data breaches and privilege escalation scenarios. An attacker exploiting this vulnerability could gain access to sensitive information that would otherwise be protected by account disablement policies, which are typically implemented to prevent access during maintenance periods, after security incidents, or when accounts are compromised. This vulnerability directly violates the principle of least privilege and can enable lateral movement within networks where disabled accounts might still contain access to critical systems or data repositories. The flaw essentially renders account disablement policies ineffective, undermining the security posture of systems relying on proper account lifecycle management.
This vulnerability aligns with CWE-287, which addresses improper authentication issues in software systems, specifically focusing on authentication bypass conditions that occur when systems fail to properly validate account status during authentication processes. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and credential access, particularly T1078 which covers valid accounts and T1550 which addresses use of stolen credentials. Organizations utilizing libpam4j for authentication in their java applications face significant risk of exploitation, as the vulnerability can be leveraged to bypass account disablement controls that are standard security practices.
The recommended mitigation strategy involves immediate upgrading of libpam4j to version 1.9 or later, where the account validation logic has been properly implemented to check account status before granting authentication access. System administrators should also implement additional monitoring controls to detect unauthorized authentication attempts against disabled accounts, though this represents a reactive measure rather than a comprehensive fix. Organizations should conduct thorough vulnerability assessments to identify all systems utilizing affected versions of libpam4j and ensure proper patch management protocols are in place. Additionally, implementing multi-factor authentication and continuous monitoring of authentication events can help detect and prevent exploitation attempts against this vulnerability, while proper account lifecycle management practices should be reinforced to minimize the risk of compromised accounts being enabled or reactivated without proper security review processes.