CVE-2018-9172 in File Upload Plugin
Summary
by MITRE
The Iptanus WordPress File Upload plugin before 4.3.3 for WordPress mishandles shortcode attributes.
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Analysis
by VulDB Data Team • 06/18/2024
The CVE-2018-9172 vulnerability affects the Iptanus WordPress File Upload plugin version 4.3.2 and earlier, representing a critical security flaw that undermines the integrity of WordPress installations. This vulnerability stems from improper handling of shortcode attributes within the plugin's file upload functionality, creating a potential attack vector that could allow malicious actors to exploit the system. The issue specifically manifests when the plugin processes user-supplied shortcode parameters, which are commonly used to embed dynamic content within WordPress posts and pages.
The technical flaw resides in the plugin's insufficient validation and sanitization of shortcode attributes, which enables attackers to inject malicious code or manipulate the file upload process. When WordPress processes shortcodes containing unvalidated parameters, the plugin fails to properly escape or filter these inputs before they are processed, creating a path for code injection attacks. This vulnerability falls under the CWE-20 category of Improper Input Validation, specifically manifesting as a weakness in how the plugin handles user-provided data within shortcode contexts. The improper handling of shortcode attributes creates a direct pathway for attackers to bypass security controls that would normally prevent unauthorized file uploads or execution of malicious code.
The operational impact of this vulnerability extends beyond simple file upload manipulation, as it can potentially enable attackers to execute arbitrary code on vulnerable WordPress installations. An attacker could leverage this flaw to upload malicious files, gain unauthorized access to the system, or establish persistent backdoors. The vulnerability affects WordPress installations where the Iptanus File Upload plugin is active, making it particularly dangerous in environments where multiple users have the ability to create or edit content. The attack surface is significant since shortcodes are frequently used throughout WordPress sites, and the vulnerability can be exploited through various vectors including blog posts, pages, or even comment sections where shortcodes might be processed. This flaw aligns with ATT&CK technique T1190 for Exploit Public-Facing Application and T1059.001 for Command and Scripting Interpreter, as it allows for remote code execution through improperly validated input parameters.
Mitigation strategies for CVE-2018-9172 require immediate action to address the vulnerability. The primary solution involves upgrading the Iptanus WordPress File Upload plugin to version 4.3.3 or later, which contains the necessary patches to properly validate and sanitize shortcode attributes. System administrators should also implement additional security measures including restricting file upload capabilities, implementing proper input validation at multiple layers, and monitoring for suspicious shortcode usage patterns. Network security controls such as web application firewalls should be configured to detect and block attempts to exploit this vulnerability, particularly targeting the specific shortcode parameters used by the plugin. Regular security audits and penetration testing should be conducted to identify similar vulnerabilities in other plugins or themes, as this issue demonstrates the importance of proper input handling in WordPress environments. The vulnerability serves as a reminder of the critical need for secure coding practices and proper validation of user inputs, particularly in plugins that handle file operations or process dynamic content through shortcodes.