CVE-2024-8338: Hfo4 Shudong-share RCE Vulnerability

CVE-2024-8338 Overview

CVE-2024-8338 is an unrestricted file upload vulnerability in HFO4 shudong-share version 2.4.7. The flaw resides in the /includes/fileReceive.php script within the File Extension Handler component. Attackers can manipulate the file argument to upload arbitrary files to the server without proper extension validation. The vulnerability requires network access and low-level privileges, and no user interaction is needed. The exploit has been publicly disclosed, increasing the risk of opportunistic attacks. The affected product is no longer supported by its maintainer, meaning no official patch will be released. The vulnerability is classified under [CWE-434: Unrestricted Upload of File with Dangerous Type].

Critical Impact
Remote authenticated attackers can upload arbitrary files, potentially leading to web shell deployment and remote code execution on affected shudong-share deployments.

Affected Products

HFO4 shudong-share 2.4.7
File Extension Handler component (/includes/fileReceive.php)
End-of-life software: no vendor support or patches available

Discovery Timeline

2024-08-30 - CVE-2024-8338 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-8338

Vulnerability Analysis

The vulnerability exists in the fileReceive.php handler responsible for processing incoming file uploads in shudong-share 2.4.7. The application accepts a file parameter and processes the upload without adequately validating the file extension or MIME type. This allows an attacker to submit files with dangerous extensions such as .php, .phtml, or other server-executable types. Once written to a web-accessible directory, these files can be requested directly, resulting in server-side code execution under the web server's privileges. Because shudong-share is a file-sharing application, upload endpoints are exposed by design, expanding the attack surface. The vulnerability has an EPSS probability of 0.503% (40.43 percentile), indicating moderate real-world exploitation likelihood.

Root Cause

The root cause is missing or insufficient validation of file extensions in the File Extension Handler. The fileReceive.php component trusts client-supplied filename metadata and does not enforce an allow-list of safe extensions. Combined with writing uploads into a location served by the PHP interpreter, this converts an upload primitive into arbitrary code execution.

Attack Vector

The attack is remote and network-based. An attacker with low-privilege authenticated access submits a crafted multipart upload request to /includes/fileReceive.php, setting the file argument to a malicious PHP payload. After upload, the attacker requests the uploaded resource through the web server to trigger execution. Refer to the GitHub CVE Analysis and VulDB entry #276217 for reproduction details.

No verified proof-of-concept code is republished here. The vulnerability mechanism is described in prose above.

Detection Methods for CVE-2024-8338

Indicators of Compromise

Unexpected .php, .phtml, .phar, or .jsp files in shudong-share upload directories
POST requests to /includes/fileReceive.php with unusual filename or content-type headers
Outbound network connections initiated by the web server process shortly after upload events
New files owned by the web server user (www-data, apache, nginx) in shared directories

Detection Strategies

Inspect web server access logs for POST requests to /includes/fileReceive.php followed by GET requests to newly created files
Deploy web application firewall (WAF) rules that block uploads with executable extensions to shudong-share endpoints
Monitor filesystem changes in upload directories using integrity monitoring tools
Correlate upload events with subsequent process creation by the web server

Monitoring Recommendations

Enable verbose PHP and web server logging on hosts running shudong-share
Alert on execution of interpreters (php, sh, bash) as child processes of the web server
Track file writes into directories served by the HTTP daemon
Baseline normal upload patterns and flag deviations in file type or volume

How to Mitigate CVE-2024-8338

Immediate Actions Required

Decommission shudong-share 2.4.7 deployments; the product is unmaintained and will not receive patches
Restrict network access to any remaining instances using firewall or reverse proxy allow-lists
Audit upload directories for existing web shells or unexpected server-side scripts
Rotate credentials for any accounts that had access to the vulnerable application

Patch Information

No official patch is available. The vendor no longer supports HFO4 shudong-share. Organizations still running version 2.4.7 should migrate to an actively maintained file-sharing platform. Consult the VulDB advisory for the latest tracking information.

Workarounds

Place shudong-share behind a WAF configured to reject uploads with executable extensions
Configure the web server to disable script execution within upload directories using php_admin_flag engine off or equivalent directives
Enforce strict extension allow-lists at the reverse proxy layer
Isolate the application on a dedicated host with minimal privileges and no outbound internet access

bash

# Example nginx configuration to disable script execution in upload paths
location ~ ^/uploads/ {
    location ~ \.(php|phtml|phar|php[0-9]+)$ {
        deny all;
        return 403;
    }
}