CVE-2014-2064 in Jenkins
Summary
by MITRE
The loadUserByUsername function in hudson/security/HudsonPrivateSecurityRealm.java in CloudBees Jenkins before 1.551 and LTS before 1.532.2 allows remote attackers to determine whether a user exists via vectors related to failed login attempts.
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Analysis
by VulDB Data Team • 03/30/2022
The vulnerability identified as CVE-2014-2064 represents a significant information disclosure flaw within the CloudBees Jenkins continuous integration platform. This weakness resides in the loadUserByUsername function implementation within the HudsonPrivateSecurityRealm.java file, affecting Jenkins versions prior to 1.551 and LTS versions prior to 1.532.2. The vulnerability stems from the application's inconsistent handling of authentication failure responses, which inadvertently reveals user account existence to unauthenticated attackers through timing variations in system responses.
The technical implementation flaw manifests when remote attackers exploit the authentication mechanism to determine whether specific user accounts exist within the Jenkins system. The vulnerability operates through failed login attempts where the system provides different response times or error messages depending on whether the username exists in the user database. This timing discrepancy creates a side-channel attack vector that allows attackers to perform user enumeration attacks, effectively mapping out valid user accounts within the Jenkins environment. The flaw aligns with CWE-203, which addresses the disclosure of information to an unauthorized actor through timing variations in system responses, and represents a classic example of insecure direct object reference vulnerability where the system's behavior reveals sensitive information.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with crucial intelligence for subsequent attack phases. Once valid user accounts are identified through enumeration, attackers can focus their efforts on credential brute-forcing or password spraying attacks against known accounts, significantly increasing their chances of successful unauthorized access. This vulnerability particularly affects Jenkins installations where user enumeration could lead to privilege escalation or lateral movement within the CI/CD infrastructure, especially when Jenkins serves as a central authentication point for development teams or integrates with other systems. The security implications align with ATT&CK technique T1078.004, which covers valid accounts obtained through credential access, as this vulnerability enables attackers to discover valid credentials through account enumeration rather than traditional brute force methods.
Mitigation strategies for CVE-2014-2064 primarily focus on upgrading to patched versions of Jenkins where the authentication mechanism has been hardened to provide consistent response times regardless of whether user accounts exist. Organizations should implement rate limiting and account lockout mechanisms to prevent automated enumeration attempts, while also ensuring that authentication failure responses are consistent and do not vary based on account existence. Security configurations should include disabling unnecessary user enumeration features and implementing proper logging to detect suspicious authentication patterns. The vulnerability demonstrates the importance of implementing constant-time authentication responses as outlined in security best practices, where system behavior should not vary based on the existence of specific objects or accounts, thereby preventing attackers from gaining intelligence through timing-based side-channel attacks.