CVE-2005-4208 in Flatnuke
Summary
by MITRE
Directory traversal vulnerability in Flatnuke 2.5.6 allows remote attackers to access arbitrary files via a .. (dot dot) and null byte (%00) in the id parameter of the read module.
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Analysis
by VulDB Data Team • 07/05/2025
The directory traversal vulnerability identified as CVE-2005-4208 affects Flatnuke version 2.5.6, a content management system that was widely used in web environments during the early 2000s. This vulnerability resides within the read module of the application and represents a classic path traversal flaw that enables malicious actors to access files outside the intended directory structure. The vulnerability specifically manifests when the application fails to properly sanitize user input provided through the id parameter, creating an opportunity for attackers to manipulate file access paths.
The technical implementation of this vulnerability leverages the combination of directory traversal sequences using dot dot notation followed by null byte encoding. When an attacker crafts a malicious request containing .. (dot dot) characters along with %00 null byte sequences in the id parameter, the application processes these inputs without adequate validation, allowing the attacker to navigate to arbitrary directories within the file system. This flaw directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal. The null byte injection aspect of this vulnerability also aligns with CWE-170, addressing issues related to improper handling of null bytes in input validation.
The operational impact of this vulnerability extends beyond simple unauthorized file access, as it can potentially lead to complete system compromise. Attackers could exploit this weakness to read sensitive configuration files, database credentials, application source code, and other confidential information stored on the web server. The vulnerability is particularly dangerous because it allows attackers to bypass normal access controls and potentially access system files that should remain protected. This type of vulnerability creates opportunities for further exploitation, including privilege escalation, data exfiltration, and the establishment of persistent access points within the compromised environment. The attack surface is significantly broadened by the fact that this vulnerability exists in a web-based content management system, which typically has direct access to server resources and user data.
Security practitioners should implement multiple layers of mitigation to address this vulnerability. The primary defense mechanism involves input validation and sanitization of all user-provided parameters, particularly those used in file access operations. Implementing proper parameter validation that rejects or encodes directory traversal sequences and null byte characters represents the most effective immediate solution. Additionally, the principle of least privilege should be enforced by ensuring that web applications operate with minimal required permissions and that sensitive files are stored outside the web root directory. System administrators should also deploy web application firewalls and intrusion detection systems that can identify and block malicious requests containing known attack patterns. The vulnerability demonstrates the critical importance of secure coding practices and input validation, as outlined in the OWASP Top Ten and MITRE ATT&CK framework, where this type of vulnerability would be categorized under T1059 for command and scripting interpreters and T1566 for malicious file execution. Organizations should also conduct regular security assessments and vulnerability scanning to identify similar weaknesses in their web applications and ensure that all systems are properly patched and updated.