CVE-2016-4313 in eXtplorer
Summary
by MITRE
Directory traversal vulnerability in unzip/extract feature in eXtplorer 2.1.9 allows remote attackers to execute arbitrary files via a .. (dot dot) in an archive file.
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Analysis
by VulDB Data Team • 01/30/2025
The vulnerability identified as CVE-2016-4313 represents a critical directory traversal flaw within the eXtplorer 2.1.9 file management system, specifically affecting the unzip and extract functionality. This vulnerability resides in the archive handling component of the application, where improper input validation allows malicious actors to manipulate file paths during extraction operations. The flaw enables remote attackers to navigate outside the intended directory boundaries and potentially execute arbitrary files on the target system. The vulnerability stems from insufficient sanitization of file paths contained within archive files, particularly when the archive contains entries with directory traversal sequences such as .. (dot dot) components. This weakness directly violates security principles by failing to properly validate and sanitize user-supplied input before processing it within the application's file system operations. The vulnerability is classified under CWE-22 as "Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')" which is a well-known and frequently exploited class of vulnerability in web applications and file handling systems.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious archive file containing file entries with traversal sequences that bypass normal path validation mechanisms. During the extraction process, the eXtplorer application fails to properly resolve and validate the target paths, allowing the attacker to specify arbitrary file locations where extracted files should be placed. This can result in overwriting critical system files, creating backdoor access points, or executing malicious code within the context of the web server process. The vulnerability is particularly dangerous because it operates at the file system level, potentially allowing attackers to escalate privileges and gain persistent access to the target environment. The attack vector is remote and requires no authentication, making it highly attractive to threat actors seeking to compromise systems running vulnerable versions of eXtplorer.
The operational impact of CVE-2016-4313 extends beyond simple file manipulation to encompass significant security implications for affected systems. Organizations running vulnerable eXtplorer installations face potential data breaches, system compromise, and unauthorized access to sensitive information stored within the file management environment. The vulnerability can be exploited to upload and execute malicious files, potentially leading to complete system compromise and lateral movement within the network. Attackers can leverage this weakness to establish persistent backdoors, exfiltrate data, or use the compromised system as a launch point for further attacks. The vulnerability affects not only the immediate file system but also the broader security posture of systems that rely on eXtplorer for file management and administrative tasks. This aligns with ATT&CK technique T1059.007 for "Command and Scripting Interpreter: PowerShell" and T1078.004 for "Valid Accounts: Cloud Accounts" when considering the potential for privilege escalation and access to cloud-based resources.
Mitigation strategies for CVE-2016-4313 should prioritize immediate patching of affected eXtplorer installations to the latest secure versions that address the directory traversal vulnerability. Organizations must implement comprehensive input validation and sanitization measures for all file path operations, particularly within archive handling components. Network segmentation and access controls should be enforced to limit exposure of vulnerable systems to untrusted networks and users. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other file management systems and applications. The implementation of Web Application Firewalls and intrusion detection systems can provide additional layers of protection against exploitation attempts. Security monitoring should be enhanced to detect suspicious file extraction activities and unauthorized file system modifications. System administrators should also consider disabling unnecessary file extraction features when possible and implementing strict file type and path validation policies to prevent exploitation of similar vulnerabilities in other components of the application stack.