CVE-2006-3360 in phpSysInfo
Summary
by MITRE • 01/25/2023
Directory traversal vulnerability in index.php in phpSysInfo 2.5.1 allows remote attackers to determine the existence of arbitrary files via a .. (dot dot) sequence and a trailing null (%00) byte in the lng parameter, which will display a different error message if the file exists.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 04/01/2026
The vulnerability identified as CVE-2006-3360 represents a directory traversal flaw within the phpSysInfo 2.5.1 web application that exposes sensitive information through improper input validation. This issue specifically affects the index.php file where the lng parameter fails to properly sanitize user-supplied input containing directory traversal sequences combined with null byte termination. The vulnerability operates by allowing attackers to manipulate the lng parameter through concatenation of dot-dot sequences followed by a null byte, which creates a condition where the application's error handling behavior differs between existing and non-existing files. When an attacker submits a crafted payload with a valid file path followed by a null byte, the application's internal file access mechanism processes this input incorrectly, resulting in distinct error messages that reveal whether specific files are present on the target system.
This directory traversal vulnerability falls under the Common Weakness Enumeration category CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The flaw enables attackers to bypass normal access controls and potentially access sensitive files that should be restricted to authorized users only. The security implications extend beyond simple file existence checking since this vulnerability can be leveraged as a reconnaissance tool to map the target filesystem structure. Attackers can systematically test various file paths and observe the different error responses to build a comprehensive understanding of the underlying system configuration and potentially identify sensitive files such as configuration files, database credentials, or system binaries that may contain exploitable information.
The operational impact of this vulnerability is significant as it provides remote attackers with a method to perform reconnaissance activities without requiring authentication or direct system access. The attack vector operates entirely through web-based requests, making it particularly dangerous for publicly accessible web applications. The null byte termination technique used in the exploit is a sophisticated approach that exploits how different web servers and application frameworks handle null bytes in input parameters, particularly in older php versions where null byte injection was still a viable attack vector. This vulnerability essentially transforms a legitimate configuration parameter into a reconnaissance tool, allowing attackers to map the filesystem structure and identify potential targets for further exploitation.
Mitigation strategies for this vulnerability should focus on implementing proper input validation and sanitization for all user-supplied parameters, particularly those used for configuration or file access operations. The most effective approach involves implementing strict parameter validation that rejects any input containing directory traversal sequences or null bytes, while also implementing proper access controls that ensure applications cannot access files outside of designated directories. Organizations should also consider implementing web application firewalls that can detect and block suspicious parameter patterns, as well as regularly updating and patching phpSysInfo installations to ensure that known vulnerabilities are addressed. The remediation process should include comprehensive code review to identify similar patterns in other parameters and functions, as well as implementing proper error handling that does not leak information about file system structure to unauthorized users. Additionally, following the principle of least privilege and implementing secure coding practices that prevent user input from directly influencing file system operations will significantly reduce the risk of similar vulnerabilities occurring in the future.