CVE-2004-2052 in Thintune
Summary
by MITRE
eSeSIX Thintune thin clients running firmware 2.4.38 and earlier accept any password that begins with the actual password, which makes it easier for users to conduct brute force password guessing.
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Analysis
by VulDB Data Team • 06/25/2018
The vulnerability identified as CVE-2004-2052 affects eSeSIX Thintune thin clients operating with firmware versions 2.4.38 and earlier, presenting a significant authentication weakness that directly impacts system security. This flaw represents a classic case of improper input validation where the system fails to properly verify the complete password rather than accepting partial matches. The vulnerability stems from a design flaw in the authentication mechanism that allows attackers to successfully authenticate by providing only the initial portion of the correct password, rather than the complete credential. This behavior fundamentally undermines the security model of password-based authentication systems and creates a substantial attack surface for malicious actors.
The technical implementation of this vulnerability manifests as a credential validation issue where the firmware performs a prefix-based comparison instead of a complete string match during the authentication process. This type of flaw falls under the CWE category of CWE-254, which addresses security weaknesses related to improper input validation and authentication mechanisms. The vulnerability specifically demonstrates a weakness in the authentication protocol implementation where the system accepts partial credential matches, making the authentication process significantly weaker than intended. The flaw operates at the application layer of the thin client architecture, affecting the authentication service that validates user credentials against stored password hashes or plaintext credentials.
From an operational perspective, this vulnerability enables attackers to conduct more efficient brute force attacks against the thin client systems. The reduced complexity of password guessing means that attackers can systematically test shorter password prefixes rather than full-length credentials, dramatically reducing the time and computational resources required to gain unauthorized access. This weakness directly maps to techniques described in the MITRE ATT&CK framework under the credential access tactics, specifically targeting the credential dumping and password cracking phases of attack operations. The vulnerability essentially reduces the effective password entropy by allowing attackers to make educated guesses about the beginning of valid passwords, making password-based attacks significantly more successful.
Organizations utilizing eSeSIX Thintune thin clients with affected firmware versions face substantial risk of unauthorized system access, particularly in environments where these devices serve as primary endpoints for user authentication. The vulnerability is especially concerning in multi-user environments where attackers can potentially compromise multiple accounts by exploiting this weakness. Security administrators should consider implementing additional access controls and monitoring mechanisms to detect unusual authentication patterns that might indicate exploitation attempts. The recommended mitigation strategy involves upgrading to firmware versions that properly implement complete password validation, which addresses the underlying authentication flaw and restores proper credential verification mechanisms.
The broader implications of this vulnerability extend beyond immediate exploitation risks to highlight the importance of proper authentication protocol implementation in embedded systems and thin client architectures. This flaw demonstrates how seemingly minor implementation details in authentication systems can create significant security weaknesses that dramatically reduce system security posture. Organizations should conduct comprehensive vulnerability assessments of their thin client deployments and ensure that firmware updates are applied promptly to address known security issues. The vulnerability also underscores the need for robust security testing of embedded systems before deployment, particularly focusing on authentication mechanisms and input validation processes that form the foundation of system security controls.