CVE-2002-1460 in L-Forum
Summary
by MITRE
L-Forum 2.40 and earlier does not properly verify whether a file was uploaded or if the associated variables were set by POST (attachment, attachment_name, attachment_size and attachment_type), which allows remote attackers to read arbitrary files.
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Analysis
by VulDB Data Team • 07/01/2024
The vulnerability identified as CVE-2002-1460 affects L-Forum version 2.40 and earlier, representing a critical security flaw in the file upload and validation mechanisms of this web-based discussion platform. This issue stems from inadequate input validation and improper handling of file upload parameters, creating a pathway for malicious actors to exploit the system's file handling capabilities. The vulnerability specifically targets the attachment processing functionality where the application fails to properly verify the legitimacy of uploaded files and their associated metadata variables.
The technical flaw manifests in the application's failure to validate whether uploaded files are actually legitimate attachments or if the associated variables such as attachment_name, attachment_size, and attachment_type have been properly set through POST requests. This validation gap allows attackers to manipulate the file upload process by directly setting these variables in their HTTP requests without actually uploading files. The system accepts these manipulated parameters and processes them as if legitimate uploads had occurred, creating a condition where arbitrary file access becomes possible through crafted requests.
This vulnerability directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal attacks. The flaw enables attackers to bypass normal file upload restrictions and potentially access sensitive files on the server filesystem. From an operational perspective, this vulnerability presents a severe risk as it allows remote attackers to read arbitrary files from the server, potentially including configuration files, database credentials, application source code, and other sensitive data that could lead to further system compromise. The impact extends beyond simple information disclosure to potential privilege escalation and complete system takeover depending on the server's file permissions and the nature of accessible files.
The attack vector for this vulnerability operates through HTTP POST requests where malicious actors craft requests with manipulated attachment variables, allowing them to specify arbitrary file paths that the application will attempt to process. This type of attack aligns with ATT&CK technique T1074.001, which involves data staging through the use of remote access tools and file transfer protocols. Organizations running L-Forum versions 2.40 or earlier are particularly vulnerable as the flaw exists in the core file handling logic without proper input sanitization or parameter validation. The vulnerability's exploitation requires minimal technical expertise and can be automated, making it a significant threat to web applications that rely on file upload functionality.
Mitigation strategies for CVE-2002-1460 should focus on implementing robust input validation and parameter verification mechanisms. The most effective approach involves ensuring that all file upload parameters undergo strict validation to confirm they originate from legitimate file uploads rather than direct HTTP request manipulation. Organizations should implement proper file type checking, size validation, and ensure that uploaded files are stored in secure, isolated directories with restricted access permissions. The recommended solution includes upgrading to L-Forum version 2.41 or later, which contains the necessary patches to address this vulnerability. Additionally, implementing web application firewalls, input sanitization routines, and comprehensive logging of file upload activities can provide additional layers of protection. Security teams should also conduct regular vulnerability assessments and penetration testing to identify similar issues in other applications and ensure proper validation of all user-supplied data before processing.