CVE-2024-6439 Overview
CVE-2024-6439 is an unrestricted file upload vulnerability in SourceCodester Home Owners Collection Management System 1.0. The flaw resides in the /classes/Users.php?f=save endpoint, where the img parameter accepts attacker-controlled files without proper validation [CWE-434]. Authenticated attackers can upload arbitrary files remotely over the network. The exploit details have been publicly disclosed under VulDB identifier VDB-270167, increasing the likelihood of opportunistic attacks against exposed installations.
Critical Impact
Remote authenticated attackers can upload arbitrary files through the img parameter, potentially leading to webshell deployment and server compromise.
Affected Products
- SourceCodester Home Owners Collection Management System 1.0
- Component: /classes/Users.php (save function)
- Vulnerable parameter: img
Discovery Timeline
- 2024-07-02 - CVE-2024-6439 published to NVD
- 2024-11-21 - Last updated in NVD database
Technical Details for CVE-2024-6439
Vulnerability Analysis
The vulnerability stems from improper validation of file uploads in the save handler of Users.php. The application accepts files submitted through the img parameter without verifying file type, extension, or content. This classifies the issue as an Unrestricted Upload of File with Dangerous Type [CWE-434].
Attackers can upload executable server-side scripts such as PHP files. Once stored within the web root, the uploaded file can be requested directly, causing the web server to execute attacker-controlled code. This converts a file upload feature into a remote code execution primitive.
The attack requires network access and low-privileged authentication. No user interaction is needed beyond the upload request itself. EPSS data places the probability of exploitation activity at 0.145%.
Root Cause
The Users.php save routine fails to enforce a server-side allowlist of permitted MIME types or extensions for the img parameter. The application trusts client-supplied metadata and writes uploaded content directly to a web-accessible directory.
Attack Vector
An attacker authenticates to the application, then sends a crafted multipart POST request to /classes/Users.php?f=save. The request includes a malicious payload such as a PHP webshell submitted through the img field. Because the handler does not reject executable extensions, the file is written to a predictable location and can be invoked through a follow-up HTTP request to achieve code execution.
Technical details and reproduction steps are documented in the public disclosure at GitHub CVE Documentation and VulDB #270167.
Detection Methods for CVE-2024-6439
Indicators of Compromise
- Unexpected .php, .phtml, or .phar files in upload directories used by the Home Owners Collection Management System
- POST requests to /classes/Users.php?f=save containing non-image content in the img field
- Outbound network connections originating from the web server process to unfamiliar hosts following upload activity
- New or modified files in user avatar or image storage paths with executable permissions
Detection Strategies
- Inspect web server access logs for POST requests to /classes/Users.php?f=save followed by GET requests to newly created files in upload directories
- Apply file integrity monitoring to upload destination folders to alert on the creation of script files
- Deploy web application firewall rules to block multipart uploads containing executable extensions or PHP tags in the img parameter
Monitoring Recommendations
- Forward web server and application logs to a centralized analytics platform for correlation of upload and execution events
- Alert on web server processes spawning shells, interpreters, or network utilities after upload activity
- Track authentication events preceding upload requests to identify compromised or brute-forced accounts
How to Mitigate CVE-2024-6439
Immediate Actions Required
- Restrict access to the application to trusted networks until a vendor patch is available
- Audit upload directories for unauthorized script files and remove any suspicious artifacts
- Rotate credentials for application users, since exploitation requires authenticated access
- Disable PHP execution in directories used to store uploaded user content
Patch Information
No official vendor patch has been published for CVE-2024-6439 at the time of writing. SourceCodester has not released vendor advisories for this issue. Organizations running Home Owners Collection Management System 1.0 should treat the deployment as unpatched and apply compensating controls. Monitor the VulDB entry for updates.
Workarounds
- Configure the web server to deny execution of PHP files within upload directories using directives such as Apache php_flag engine off or equivalent location blocks in nginx
- Implement a server-side allowlist that validates uploaded files by both extension and MIME type, rejecting anything other than expected image formats
- Rename uploaded files to randomized identifiers and store them outside the web root, serving them through a controlled download handler
- Place the application behind a web application firewall configured to block script content in image upload parameters
# Apache configuration example: disable PHP execution in upload directory
<Directory "/var/www/hocms/uploads">
php_flag engine off
AddType text/plain .php .phtml .phar
Options -ExecCGI
</Directory>
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
