CVE-2019-9617 in OFCMS
Summary
by MITRE
An issue was discovered in OFCMS before 1.1.3. Remote attackers can execute arbitrary code because blocking of .jsp and .jspx files does not consider (for example) file.jsp::$DATA to the admin/ueditor/uploadFile URI.
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Analysis
by VulDB Data Team • 07/29/2023
The vulnerability identified as CVE-2019-9617 affects OFCMS versions prior to 1.1.3 and represents a critical security flaw in the file upload validation mechanism. This issue stems from inadequate filtering of file extensions and names, allowing attackers to bypass security measures through unconventional file naming techniques. The vulnerability specifically targets the admin/ueditor/uploadFile URI endpoint where the system fails to properly validate file types, creating a path for remote code execution. The flaw demonstrates a fundamental weakness in the application's input sanitization and access control mechanisms.
The technical implementation of this vulnerability exploits the Windows NTFS file system's alternate data streams feature, where file.jsp::$DATA represents an alternate data stream that can contain arbitrary content while maintaining the original file extension. This technique allows attackers to upload malicious code disguised as legitimate jsp files, bypassing the standard file extension blocking mechanisms. The system's security controls only check for direct .jsp and .jspx extensions but fail to account for these alternate data stream representations, which can contain executable code that gets processed by the application server. This approach leverages the operating system's file system capabilities rather than the application's own validation logic.
The operational impact of this vulnerability is severe as it enables remote code execution without requiring authentication or privileged access. Attackers can upload malicious files through the web interface and subsequently execute arbitrary commands on the server, potentially leading to complete system compromise. The vulnerability affects the core functionality of the content management system, allowing unauthorized users to gain persistent access and control over the server environment. This creates a significant risk for organizations relying on OFCMS for their web applications, as the attack can be executed entirely through standard web browser interactions.
Mitigation strategies should focus on implementing comprehensive file validation mechanisms that account for all possible file naming conventions and system-specific features. Organizations should upgrade to OFCMS version 1.1.3 or later where this vulnerability has been addressed through improved file extension filtering and alternate data stream detection. Additional protective measures include implementing strict file type validation at multiple layers including application-level checks, web server configurations, and file system permissions. The solution should align with CWE-434 which addresses insecure file upload vulnerabilities and follows ATT&CK technique T1190 for exploiting vulnerabilities in web applications. Network segmentation and monitoring of file upload activities should also be implemented to detect and prevent unauthorized file uploads.