CVE-2004-1421 in Autopilot
Summary
by MITRE
Multiple PHP remote file inclusion vulnerabilities (1) step_one.php, (2) step_one_tables.php, (3) step_two_tables.php in WHM AutoPilot 2.4.6.5 and earlier allow remote attackers to execute arbitrary PHP code by modifying the server_inc parameter to reference a URL on a remote web server that contains the code.
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Analysis
by VulDB Data Team • 06/23/2025
The vulnerability described in CVE-2004-1421 represents a critical remote file inclusion flaw affecting WHM AutoPilot version 2.4.6.5 and earlier. This vulnerability resides within three specific PHP scripts: step_one.php, step_one_tables.php, and step_two_tables.php, all of which are part of the AutoPilot application's installation and configuration processes. The flaw allows remote attackers to inject malicious code by manipulating the server_inc parameter through URL references pointing to external web servers containing malicious PHP code.
This vulnerability constitutes a classic remote code execution (RCE) threat that operates through improper input validation and dynamic file inclusion mechanisms. The affected application fails to properly sanitize user-supplied input parameters before using them in file inclusion operations, creating a pathway for attackers to load arbitrary PHP scripts from remote servers. The server_inc parameter serves as the primary attack vector, where an attacker can substitute legitimate server paths with malicious URLs, effectively bypassing local file access controls and executing unauthorized code on the target system.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with complete control over the affected web server. Once exploited, attackers can upload backdoors, steal sensitive data, modify system configurations, or establish persistent access points within the compromised environment. The vulnerability's remote nature means that attackers do not require physical access or local credentials to exploit the flaw, making it particularly dangerous for web applications that are publicly accessible. The affected WHM AutoPilot application likely handles sensitive server configuration data, making this vulnerability particularly attractive to threat actors seeking to compromise hosting environments.
From a cybersecurity perspective, this vulnerability aligns with CWE-88, which describes improper neutralization of special elements used in an input vector, and represents a direct violation of secure coding practices. The flaw also maps to ATT&CK technique T1190, which covers exploiting vulnerabilities in remote services through the execution of malicious code. Organizations running affected versions of WHM AutoPilot face significant risk of compromise, as the vulnerability can be exploited through simple HTTP requests without requiring complex attack chains. The exploitation process typically involves crafting malicious URLs that point to attacker-controlled servers, where PHP code is hosted and subsequently executed by the vulnerable application.
Mitigation strategies for this vulnerability include immediate patching of the affected software to version 2.4.6.6 or later, which addresses the insecure parameter handling. Additionally, implementing input validation measures such as whitelisting acceptable parameter values, disabling remote file inclusion in PHP configurations, and employing web application firewalls can provide layered protection. Security administrators should also conduct thorough vulnerability assessments to identify other potentially affected applications and ensure proper parameter sanitization throughout the codebase. The vulnerability highlights the critical importance of validating all user inputs and avoiding dynamic file inclusion operations that rely on external parameters without proper security controls.