CVE-2006-6725 in PHPBuilder
Summary
by MITRE
Multiple directory traversal vulnerabilities in PHPBuilder 0.0.2 and earlier allow remote attackers to read arbitrary files via a .. (dot dot) in the filename parameter to (1) lib/htm2php.php and (2) sitetools/htm2php.php. NOTE: The provenance of this information is unknown; the details are obtained solely from third party information.
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Analysis
by VulDB Data Team • 08/12/2018
The vulnerability described in CVE-2006-6725 represents a critical directory traversal flaw affecting PHPBuilder versions 0.0.2 and earlier. This issue stems from inadequate input validation mechanisms within the application's file handling processes, specifically in two key components: lib/htm2php.php and sitetools/htm2php.php. The vulnerability allows remote attackers to exploit the system by manipulating the filename parameter through the use of .. (dot dot) sequences, which enables them to navigate outside the intended directory boundaries and access arbitrary files on the server. This type of vulnerability falls under the common weakness enumeration CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory, also known as path traversal or directory traversal attacks. The attack vector operates by constructing malicious file paths that leverage the relative path navigation capabilities of the operating system, allowing unauthorized access to sensitive files that should remain protected within the application's designated directories.
The technical exploitation of this vulnerability demonstrates a fundamental flaw in the application's security architecture where user-supplied input is not properly sanitized or validated before being processed by the file system operations. When the filename parameter contains sequences such as ../ or ../../, the application fails to normalize or validate these inputs, resulting in the system interpreting these paths as legitimate requests rather than malicious attempts to access files outside the intended scope. This weakness directly violates the principle of least privilege and fails to implement proper access controls that should prevent unauthorized file system access. The impact extends beyond simple file reading capabilities, as attackers could potentially access configuration files, database credentials, application source code, or other sensitive information stored on the server. The vulnerability affects both the lib/htm2php.php and sitetools/htm2php.php components, indicating a systemic issue within the application's file handling logic rather than an isolated incident, suggesting that multiple attack surfaces within the application are susceptible to similar manipulation techniques.
The operational impact of CVE-2006-6725 is severe and multifaceted, as it provides attackers with the ability to exfiltrate sensitive data from the affected system without requiring authentication or elevated privileges. This vulnerability can be exploited remotely, meaning that an attacker can leverage it from any location without physical access to the system, making it particularly dangerous for web applications that are publicly accessible. The potential damage includes exposure of application source code, which could reveal implementation details and logic that attackers could then exploit for additional vulnerabilities, as well as access to configuration files that might contain database connection strings, API keys, or other sensitive credentials. The vulnerability also aligns with techniques documented in the attack pattern taxonomy under the MITRE ATT&CK framework, specifically relating to privilege escalation and credential access tactics that attackers commonly employ to gain deeper system access. Organizations running affected versions of PHPBuilder face significant risk of data breaches, system compromise, and potential regulatory compliance violations due to the exposure of sensitive information that attackers can obtain through this vulnerability.
Mitigation strategies for CVE-2006-6725 should focus on implementing robust input validation and sanitization mechanisms that prevent the use of directory traversal sequences in file path parameters. The most effective approach involves normalizing all user-supplied file paths by removing or encoding potentially dangerous characters such as .., /, and \ before processing file operations. Application developers should implement strict whitelisting of acceptable file paths and ensure that all file operations occur within predetermined, secure directories that are isolated from sensitive system components. Additionally, the application should employ proper access control mechanisms that validate user permissions before allowing file access operations. Security measures should include implementing proper file system permissions that prevent unauthorized access to sensitive directories and files, as well as regular security audits to identify and remediate similar vulnerabilities. Organizations should also consider implementing web application firewalls that can detect and block suspicious path traversal attempts, and ensure that all systems are running patched versions of PHPBuilder that address this vulnerability. The remediation process should also include comprehensive testing of file handling operations to verify that the implemented security controls effectively prevent directory traversal attacks and maintain the integrity of the application's file system access controls.