CVE-2007-3315 in YourFreeScreamer
Summary
by MITRE
Multiple PHP remote file inclusion vulnerabilities in YourFreeScreamer 1.0, when register_globals is enabled, allow remote attackers to execute arbitrary PHP code via a URL in the serverPath parameter to bodyTemplate.php in (1) templates/Classic/, (2) templates/Classic Guestbook/, (3) templates/DarkNights/, and (4) templates/Simplistic/, different vectors than CVE-2007-3271. 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 • 09/04/2018
The vulnerability described in CVE-2007-3315 represents a critical remote file inclusion flaw affecting the YourFreeScreamer 1.0 content management system. This vulnerability specifically exploits the dangerous combination of PHP's register_globals directive being enabled and improper input validation in the application's template processing functionality. The flaw manifests in four distinct template directories within the application's codebase, making it particularly widespread and difficult to contain. The vulnerability operates through the serverPath parameter in the bodyTemplate.php file, which accepts user-supplied URLs without adequate sanitization or validation, creating an exploitable pathway for remote code execution.
The technical implementation of this vulnerability stems from the insecure handling of user input within the PHP application's template rendering system. When register_globals is enabled, PHP automatically creates global variables from HTTP request parameters, effectively bypassing normal input validation mechanisms. Attackers can manipulate the serverPath parameter to include malicious URLs pointing to remote servers hosting malicious PHP code. The exploitation process typically involves crafting a specially formatted URL that, when processed by the vulnerable bodyTemplate.php script, causes the PHP interpreter to include and execute the remote code. This vulnerability directly maps to CWE-88, which describes improper neutralization of argument delimiters in a command or query, and more specifically to CWE-94, which covers the execution of arbitrary code or commands.
The operational impact of this vulnerability extends far beyond simple code execution, as it provides attackers with complete control over the affected server. Once successfully exploited, adversaries can upload additional malicious files, establish persistent backdoors, escalate privileges, and potentially use the compromised server as a launch point for further attacks within the network. The vulnerability's presence in multiple template directories increases the attack surface significantly, making it more likely that an attacker can find a working exploit path. Additionally, the fact that this vulnerability requires only a single parameter manipulation makes it particularly attractive to automated exploitation tools, increasing the risk of widespread compromise. This vulnerability directly aligns with ATT&CK technique T1190, which covers the use of remote access tools and backdoors for maintaining persistent access to compromised systems.
Mitigation strategies for CVE-2007-3315 must address both the immediate vulnerability and underlying architectural issues. The most effective immediate fix involves disabling the register_globals directive in the PHP configuration, which eliminates the primary attack vector by preventing automatic creation of global variables from HTTP parameters. Additionally, all input parameters must be properly validated and sanitized before processing, implementing proper input filtering and output encoding techniques. The application should implement a whitelist-based approach for template inclusion, rejecting any external URLs and only allowing predefined, safe template paths. Security headers should be implemented to prevent inclusion of external resources, and the application should be updated to a newer version that addresses these vulnerabilities. Network-level protections such as web application firewalls can provide additional layers of defense by monitoring for suspicious parameter patterns and blocking known malicious URL patterns. The remediation process should also include comprehensive code review to identify and fix similar vulnerabilities in other parts of the application, ensuring that the system maintains robust input validation throughout all code paths.