CVE-2018-12988 in GreenCMS
Summary
by MITRE
GreenCMS 2.3.0603 has an arbitrary file download vulnerability via an index.php?m=admin&c=media&a=downfile URI.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/29/2023
The vulnerability identified as CVE-2018-12988 affects GreenCMS version 2.3.0603 and represents a critical arbitrary file download flaw that can be exploited through a specific URI endpoint. This vulnerability resides within the content management system's administrative interface, specifically targeting the media management component that handles file operations. The affected parameter structure index.php?m=admin&c=media&a=downfile creates an attack surface where malicious actors can manipulate input parameters to request arbitrary files from the server filesystem, potentially leading to unauthorized access to sensitive system resources.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the file download functionality of the GreenCMS administration module. When the system processes requests through the downfile action, it fails to properly validate user-supplied file paths or names, allowing attackers to craft malicious requests that traverse the filesystem and download files that should remain protected. This weakness directly maps to CWE-22, known as "Improper Limitation of a Pathname to a Restricted Directory," which is a fundamental security flaw that enables path traversal attacks. The vulnerability's exploitation requires minimal prerequisites and can be executed through simple HTTP requests, making it particularly dangerous for systems that are not properly secured.
The operational impact of this vulnerability extends beyond simple unauthorized file access, as it can potentially lead to complete system compromise. Attackers can leverage this flaw to download configuration files containing database credentials, application source code, server configuration details, and other sensitive information that could be used for further exploitation. The vulnerability's presence in the administrative interface means that successful exploitation could provide attackers with elevated privileges and access to critical system components. This aligns with ATT&CK technique T1213.002, which describes "Data from Information Repositories" and represents a common attack pattern where adversaries target administrative interfaces to extract sensitive data and system information.
Security mitigation strategies for CVE-2018-12988 should focus on implementing proper input validation and access controls within the CMS. Organizations should immediately apply the vendor's patch or upgrade to a non-vulnerable version of GreenCMS to address the root cause of the vulnerability. Additionally, implementing web application firewalls with rules that block suspicious file download patterns and restricting administrative access to trusted IP addresses can provide additional defense layers. Network segmentation and monitoring of administrative interface access attempts should be implemented to detect and respond to potential exploitation attempts. The vulnerability demonstrates the critical importance of validating all user inputs and implementing proper access controls, particularly within administrative components of web applications, as recommended by security frameworks such as OWASP Top Ten and NIST cybersecurity guidelines. Regular security assessments and penetration testing should be conducted to identify similar vulnerabilities in other components of the web application stack.