CVE-2006-3987 in FileManager
Summary
by MITRE
Multiple PHP remote file inclusion vulnerabilities in index.php in Knusperleicht FileManager 1.2 and earlier allow remote attackers to execute arbitrary PHP code via a URL in the (1) dwl_download_path or (2) dwl_include_path parameters.
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Analysis
by VulDB Data Team • 07/11/2024
The vulnerability identified as CVE-2006-3987 represents a critical remote file inclusion flaw affecting Knusperleicht FileManager version 1.2 and earlier. This vulnerability resides within the index.php script and demonstrates a classic path traversal attack vector that enables remote attackers to inject and execute arbitrary PHP code on the target system. The vulnerability specifically impacts two parameter fields: dwl_download_path and dwl_include_path, both of which are susceptible to manipulation through crafted URL inputs. The flaw stems from insufficient input validation and sanitization mechanisms within the application's file handling processes, creating an exploitable condition where user-supplied data directly influences the inclusion of external files. This type of vulnerability falls under the category of CWE-88, which describes the improper neutralization of special elements used in an expression, and more specifically aligns with CWE-94, representing the execution of arbitrary code due to improper input validation. The ATT&CK framework categorizes this as a remote code execution technique under the T1059.007 sub-technique, which involves the use of scripting languages to execute commands on compromised systems. The attack surface is particularly concerning as it allows adversaries to leverage the application's legitimate file inclusion mechanisms to load malicious content from remote servers, effectively bypassing local security controls.
The technical exploitation of this vulnerability requires an attacker to craft malicious URLs containing specially formatted paths that will be processed by the vulnerable application. When the application processes these parameters, it fails to properly validate or sanitize the input, allowing the attacker to specify external URLs that point to malicious PHP scripts hosted on remote servers. The successful exploitation results in the execution of arbitrary code on the target system with the privileges of the web application process. This presents a severe operational impact as attackers can establish persistent access, escalate privileges, and potentially compromise the entire hosting environment. The vulnerability's severity is amplified by its remote nature, meaning that no local system access is required for exploitation, and it can be leveraged from any network location. Additionally, the lack of proper input filtering creates a persistent threat vector that remains viable as long as the vulnerable version remains installed, making it particularly attractive to automated attack tools and persistent threat actors. The vulnerability also demonstrates poor secure coding practices, as the application directly incorporates user-provided paths without proper validation or sanitization, violating fundamental security principles of input validation and least privilege execution.
The operational impact of this vulnerability extends beyond immediate code execution capabilities to encompass broader security implications for the affected systems. Organizations running vulnerable versions of Knusperleicht FileManager face potential data breaches, system compromise, and unauthorized access to sensitive information stored within the application's scope. The vulnerability can serve as a stepping stone for attackers to conduct further reconnaissance and lateral movement within the network, as the compromised system becomes a potential launch point for additional attacks. Furthermore, the vulnerability's persistence means that even if initial exploitation is mitigated, the underlying flaw remains present and can be re-exploited by attackers. System administrators must consider the potential for persistent backdoors and the difficulty of complete remediation, as compromised systems may retain malicious code or configuration changes. The vulnerability also impacts compliance requirements, as it creates potential audit trail issues and may violate regulatory standards that mandate secure application development practices. Organizations should also consider the broader implications for their security posture, as the presence of such vulnerabilities often indicates a lack of proper security testing and code review processes within the development lifecycle. Mitigation efforts must include immediate patching, network segmentation to limit attack surface, and implementation of web application firewalls to detect and prevent exploitation attempts. The vulnerability serves as a reminder of the critical importance of input validation, proper secure coding practices, and regular security assessments to prevent similar issues from occurring in other applications and systems.