CVE-2005-1821 in PowerDownload
Summary
by MITRE
PHP remote file inclusion vulnerability in pdl_header.inc.php in PowerDownload 3.0.2 and 3.0.3 allows remote attackers to execute arbitrary PHP code via the incdir parameter to downloads.php.
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Analysis
by VulDB Data Team • 10/27/2025
The vulnerability identified as CVE-2005-1821 represents a critical remote file inclusion flaw in the PowerDownload content management system version 3.0.2 and 3.0.3. This issue resides within the pdl_header.inc.php file and specifically affects the downloads.php script which processes the incdir parameter. The vulnerability stems from inadequate input validation and sanitization mechanisms that fail to properly restrict user-supplied data from being directly incorporated into file inclusion operations. This allows malicious actors to manipulate the application's behavior by injecting arbitrary file paths or URLs, thereby bypassing normal access controls and executing unauthorized code within the target environment.
The technical exploitation of this vulnerability occurs through a classic remote file inclusion attack vector where an attacker crafts a malicious URL containing the incdir parameter pointing to a remote server hosting malicious PHP code. When the vulnerable application processes this parameter without proper validation, it includes and executes the attacker-controlled file, effectively granting remote code execution capabilities. This flaw directly maps to CWE-88, which describes improper neutralization of special elements used in an expression, and CWE-94, which covers execution of arbitrary code due to improper input validation. The vulnerability demonstrates a fundamental lack of input sanitization and proper parameter validation, allowing attackers to inject malicious file paths that are then processed by the application's include or require functions.
The operational impact of this vulnerability extends far beyond simple code execution, as it provides attackers with complete control over the affected server. Once exploited, attackers can upload additional malicious files, establish persistent backdoors, escalate privileges, and potentially use the compromised server as a launchpad for further attacks against the internal network. The vulnerability affects the confidentiality, integrity, and availability of the system, as attackers can read sensitive data, modify application behavior, and potentially disrupt services. From an ATT&CK framework perspective, this vulnerability enables multiple techniques including T1059 for command and scripting interpreter, T1105 for remote file execution, and T1078 for valid accounts, as attackers can leverage the compromised system to maintain persistence and move laterally within the network infrastructure.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security improvements. The primary solution involves updating to a patched version of PowerDownload that properly validates and sanitizes the incdir parameter, ensuring that only legitimate local file paths are accepted. Organizations should implement input validation that restricts the incdir parameter to predefined safe directories and rejects any URLs or external references. Additionally, disabling remote file inclusion features entirely by configuring the php.ini directive allow_url_include to off provides an additional layer of protection. Security best practices recommend implementing proper parameter validation, using whitelisting approaches for file inclusion operations, and regularly updating all third-party components to address known vulnerabilities. Network segmentation and intrusion detection systems should also be deployed to monitor for suspicious file inclusion patterns and prevent exploitation attempts from reaching the vulnerable application.