CVE-2005-2635 in phpPgAds
Summary
by MITRE
Multiple directory traversal vulnerabilities in phpAdsNew and phpPgAds before 2.0.6 allow remote attackers to include arbitrary files via a .. (dot dot) in the (1) layerstyle parameter to adlayer.php or (2) language parameter to js-form.php.
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Analysis
by VulDB Data Team • 06/08/2019
The vulnerability described in CVE-2005-2635 represents a critical directory traversal flaw affecting phpAdsNew and phpPgAds versions prior to 2.0.6. This security weakness stems from inadequate input validation mechanisms within the web applications' file inclusion processes, specifically targeting two distinct script endpoints that handle user-supplied parameters. The vulnerability enables remote attackers to manipulate file paths through the use of directory traversal sequences, creating a pathway for unauthorized file access and potential system compromise. The affected parameters include the layerstyle parameter in adlayer.php and the language parameter in js-form.php, both of which are processed without proper sanitization of special characters that could alter the intended file resolution paths.
The technical exploitation of this vulnerability relies on the ability to inject directory traversal sequences using the .. (dot dot) notation into the targeted parameters. When these parameters are processed by the vulnerable applications, the .. sequences can navigate upward through the directory structure, potentially allowing attackers to access files outside the intended web root or application directory boundaries. This flaw directly maps to CWE-22, which defines the weakness of improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal. The vulnerability operates at the application layer where user input is directly incorporated into file system operations without adequate validation or sanitization, creating a direct pathway for attackers to access sensitive files that should remain protected.
The operational impact of this vulnerability extends beyond simple file disclosure, as it can potentially enable attackers to execute arbitrary code or access sensitive system information. Remote attackers could leverage this weakness to access configuration files containing database credentials, application secrets, or other sensitive data that might be stored in accessible locations. The attack surface is particularly concerning given that these applications were commonly used for web advertising and content management, often running on web servers with potentially elevated privileges. This vulnerability could allow attackers to escalate their privileges by accessing system files or configuration data that might contain authentication tokens, database connection strings, or other critical system information. The implications align with ATT&CK technique T1083, which covers the discovery of system information through directory listing and file access methods.
Mitigation strategies for CVE-2005-2635 should focus on immediate application updates to version 2.0.6 or later, where the directory traversal vulnerabilities have been addressed through proper input validation and parameter sanitization. Organizations should implement comprehensive input validation mechanisms that filter out or escape special characters including the .. sequence before processing user-supplied parameters. The recommended approach includes implementing whitelisting of allowed parameters, using absolute path resolution for file operations, and ensuring that all user input is properly sanitized before being used in file system operations. Additionally, organizations should consider implementing web application firewalls that can detect and block directory traversal attempts, as well as conducting regular security audits to identify and remediate similar vulnerabilities in other web applications. The fix should also include proper access controls and least privilege principles to limit the impact of any successful exploitation attempts, ensuring that even if an attacker gains access to file system operations, they cannot escalate privileges or access unauthorized resources.