CVE-2024-7495: Laravel Accounting System RCE Vulnerability

CVE-2024-7495 Overview

CVE-2024-7495 is an unrestricted file upload vulnerability in itsourcecode Laravel Accounting System 1.0. The flaw resides in the app/Http/Controllers/HomeController.php file, where manipulation of the image argument allows attackers to upload arbitrary files without proper validation [CWE-434]. The vulnerability is remotely exploitable and requires only low-privilege authentication. Public disclosure of the exploit details increases the risk of opportunistic attacks against exposed instances.

Critical Impact

Authenticated remote attackers can upload arbitrary files through the image parameter, potentially leading to web shell deployment and server compromise.

Affected Products

• itsourcecode Laravel Accounting System 1.0
• Component: app/Http/Controllers/HomeController.php
• Vendor: itsourcecode

Discovery Timeline

• 2024-08-06 - CVE-2024-7495 published to NVD with VulDB identifier VDB-273621
• 2024-08-19 - Last updated in NVD database

Technical Details for CVE-2024-7495

Vulnerability Analysis

The vulnerability exists in the image upload functionality handled by HomeController.php. The controller accepts user-supplied data through the image parameter without enforcing restrictions on file type, content, or extension. This classifies the issue as an Unrestricted Upload of File with Dangerous Type [CWE-434].

An authenticated attacker can submit a crafted HTTP request containing a malicious file disguised as an image. Because the application does not validate the MIME type, extension, or magic bytes, server-executable files such as PHP scripts can be written to the web root. Once uploaded, the attacker can request the file directly to trigger execution within the application context.

The EPSS score of 0.27% reflects current exploitation probability, but public disclosure of technical details on VulDB lowers the barrier for adversaries seeking to weaponize the flaw.

Root Cause

The root cause is missing server-side input validation on file uploads. The application trusts client-supplied metadata for the image parameter and writes uploaded content to disk without restricting allowed extensions, verifying file signatures, or storing files outside the web-accessible directory.

Attack Vector

Exploitation requires network access to the application and low-privilege authentication. The attacker submits a POST request to the vulnerable endpoint with a file payload assigned to the image field. The malicious file is stored on the server, and the attacker then issues a follow-up HTTP request to execute the uploaded code. No user interaction is required beyond the attacker's authenticated session.

Technical analysis of the vulnerability is available in the GitHub CVE Analysis and the VulDB entry #273621.

Detection Methods for CVE-2024-7495

Indicators of Compromise

• Files with executable extensions (.php, .phtml, .phar) present in upload directories used by the accounting application
• HTTP POST requests to upload endpoints in HomeController.php containing non-image content in the image parameter
• Outbound network connections originating from the web server process following recent upload activity
• New or modified files in web-accessible directories with timestamps correlating to suspicious POST requests

Detection Strategies

• Inspect web server access logs for POST requests to image upload routes with unusual content lengths or non-standard Content-Type headers
• Monitor the file system for new PHP files written under user-controlled upload paths
• Review application logs for authenticated sessions performing repeated uploads with varying file extensions
• Deploy file integrity monitoring on directories writable by the web server user

Monitoring Recommendations

• Enable verbose logging on the Laravel application to capture upload requests including filename, MIME type, and authenticated user
• Alert on web server process spawning shell interpreters such as sh, bash, or cmd
• Track HTTP response codes and request patterns indicative of webshell interaction following file upload events

How to Mitigate CVE-2024-7495

Immediate Actions Required

• Restrict access to the Laravel Accounting System to trusted networks until a vendor patch is available
• Audit the uploads directory and the application web root for unauthorized files created since deployment
• Disable PHP execution in directories that store user-uploaded content using web server configuration
• Revoke and rotate credentials for any accounts that may have been used to access the application

Patch Information

No vendor advisory or official patch has been published for CVE-2024-7495 at the time of NVD update on 2024-08-19. Organizations running itsourcecode Laravel Accounting System 1.0 should consider this an unpatched vulnerability and apply compensating controls. Refer to the VulDB submission #385829 for ongoing tracking.

Workarounds

• Implement server-side allowlisting in HomeController.php to accept only specific image MIME types and extensions such as .jpg, .png, and .gif
• Validate uploaded file magic bytes against expected image signatures before writing to disk
• Store uploaded files outside the web root and serve them through a controlled handler that sets non-executable Content-Type headers
• Deploy a web application firewall rule to block POST requests containing PHP tags or executable payloads in multipart form fields

# Apache configuration to disable PHP execution in upload directory
<Directory "/var/www/laravel-accounting/public/uploads">
    php_flag engine off
    <FilesMatch "\.(php|phtml|phar|php3|php4|php5|php7)$">
        Require all denied
    </FilesMatch>
</Directory>