CVE-2002-1064 in Jana Web Server
Summary
by MITRE
Thomas Hauck Jana Server 2.x through 2.2.1, and 1.4.6 and earlier, generates different responses for valid and invalid usernames, which allows remote attackers to identify valid users on the server.
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Analysis
by VulDB Data Team • 09/09/2025
The vulnerability identified as CVE-2002-1064 affects Thomas Hauck Jana Server versions 1.4.6 and earlier, as well as 2.x through 2.2.1, presenting a significant security risk through improper error handling mechanisms. This flaw manifests in the server's response behavior where it provides different responses for valid and invalid usernames, creating a predictable pattern that can be exploited by remote attackers to enumerate valid user accounts. The issue stems from the server's lack of consistent error messaging when processing authentication requests, which violates fundamental security principles of providing uniform responses regardless of input validity.
The technical implementation of this vulnerability operates through the server's authentication mechanism where it differentiates between valid and invalid user credentials in its response handling. When an attacker submits a username, the server responds with distinct error messages or response codes that vary based on whether the username exists in the system. This differential response behavior creates a side-channel attack vector that allows malicious actors to determine valid user accounts through systematic testing and observation of response variations. The vulnerability directly relates to CWE-200, which addresses information exposure through improper error handling, and represents a classic case of information leakage that undermines authentication security.
The operational impact of this vulnerability extends beyond simple user enumeration, as it provides attackers with a foundational foothold for subsequent attacks. Once valid usernames are identified, attackers can proceed with targeted brute force attempts, credential stuffing attacks, or social engineering campaigns with significantly higher success rates. The vulnerability affects the server's ability to maintain confidentiality of user account information and undermines the principle of least privilege by exposing user account existence to unauthorized parties. This issue particularly impacts organizations relying on the Jana Server for authentication services, as it creates an attack surface that can be leveraged for privilege escalation or account takeover attempts.
Mitigation strategies for CVE-2002-1064 require immediate implementation of consistent error handling across all authentication endpoints. Organizations should ensure that all authentication requests return identical responses regardless of whether the username exists in the system, eliminating any differential behavior that could reveal user account information. This approach aligns with ATT&CK technique T1565.001, which involves data manipulation through consistent error responses to prevent information leakage. System administrators should also implement rate limiting and account lockout mechanisms to prevent automated enumeration attempts, while ensuring that server responses do not contain any identifying information about user account status. The most effective long-term solution involves updating to patched versions of the Jana Server software where the inconsistent error handling has been corrected and all authentication responses are normalized to maintain security through obscurity principles.