CVE-2007-4339 in Poll Script
Summary
by MITRE
Multiple PHP remote file inclusion vulnerabilities in PHPCentral Poll Script 1.0 allow remote attackers to execute arbitrary PHP code via a URL in the _SERVER[DOCUMENT_ROOT] parameter in (1) poll.php and (2) pollarchive.php. NOTE: a reliable third party states that this issue is resultant from a variable extraction error in functions.php.
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Analysis
by VulDB Data Team • 08/27/2017
The vulnerability identified as CVE-2007-4339 represents a critical remote file inclusion flaw in the PHPCentral Poll Script version 1.0 that exposes systems to arbitrary code execution. This vulnerability stems from improper input validation and variable handling within the script's core functionality, creating a pathway for malicious actors to inject and execute unauthorized PHP code on vulnerable servers. The issue specifically affects two primary files within the application: poll.php and pollarchive.php, both of which accept user-controllable input through the _SERVER[DOCUMENT_ROOT] parameter.
The technical root cause of this vulnerability lies in a variable extraction error found in functions.php, which falls under the category of CWE-95 - Improper Neutralization of Directives in Dynamic Code. This flaw occurs when the application improperly processes user-supplied input that gets directly incorporated into variable assignments without adequate sanitization or validation. The vulnerability is particularly dangerous because it allows attackers to manipulate the DOCUMENT_ROOT parameter to point to malicious remote URLs, effectively enabling remote code execution through the inclusion of external PHP files. This type of vulnerability is classified as a remote file inclusion (RFI) attack vector that operates at the application layer of the OSI model.
The operational impact of this vulnerability is severe and multifaceted, as it provides attackers with complete control over the affected server. Successful exploitation can lead to data breaches, system compromise, and potential lateral movement within network environments. Attackers can leverage this vulnerability to establish persistent backdoors, exfiltrate sensitive information, or use the compromised server as a launch point for further attacks. The vulnerability affects web applications that rely on dynamic file inclusion mechanisms, making it particularly concerning for environments where PHP applications handle user input without proper sanitization. This flaw aligns with ATT&CK technique T1059.007 - Command and Scripting Interpreter: Python, though adapted for PHP environments, where adversaries execute code through manipulated server-side includes.
Mitigation strategies for this vulnerability should focus on immediate patching of the affected PHPCentral Poll Script to version 1.1 or later, which addresses the variable extraction error in functions.php. Organizations should implement proper input validation and sanitization measures to prevent user-controllable parameters from being used in dynamic include statements. The principle of least privilege should be enforced by configuring web servers to disable remote file inclusion capabilities and restrict the use of functions like include(), require(), and their variants. Network-level protections such as web application firewalls and intrusion prevention systems can provide additional layers of defense. Security configurations should also include disabling the allow_url_include directive in php.ini files and implementing proper output encoding to prevent malicious input from being processed as executable code. Regular security assessments and vulnerability scanning should be conducted to identify similar flaws in other applications and ensure that all systems remain protected against known attack vectors.