CVE-2025-58048: Paymenter File Upload RCE Vulnerability

CVE-2025-58048 Overview

CVE-2025-58048 is a critical arbitrary file upload vulnerability affecting Paymenter, a free and open-source webshop solution designed for hosting services. The vulnerability exists in the ticket attachments functionality, which allows malicious authenticated users to upload arbitrary files to the server without proper validation or restrictions.

This vulnerability (CWE-434: Unrestricted Upload of File with Dangerous Type) enables attackers to bypass file upload security controls, potentially leading to remote code execution on the underlying server. The impact is severe as successful exploitation could result in sensitive data extraction from the database, credential theft from configuration files, and arbitrary system command execution under the web server user context.

Critical Impact

Authenticated attackers can upload malicious files through the ticket attachment feature, potentially achieving remote code execution and full system compromise on servers running vulnerable Paymenter installations.

Affected Products

• Paymenter versions prior to 1.2.11
• Paymenter installations with ticket attachments functionality enabled
• Self-hosted Paymenter deployments using default nginx configurations

Discovery Timeline

• 2025-08-28 - CVE-2025-58048 published to NVD
• 2025-08-29 - Last updated in NVD database

Technical Details for CVE-2025-58048

Vulnerability Analysis

The vulnerability resides in Paymenter's ticket attachment handling mechanism implemented via the Livewire framework. The application uses the WithFileUploads trait from Livewire's file upload support system without implementing adequate validation of uploaded file types, extensions, or content. This architectural flaw allows authenticated users to upload arbitrary files, including executable scripts such as PHP web shells.

When a malicious file is uploaded through the ticket creation or ticket response functionality, the file is stored in the /storage/ directory and can potentially be accessed and executed directly by the web server. This transforms what appears to be a simple file upload feature into a critical remote code execution vector.

The attack surface requires only low-privileged authenticated access, as any user capable of creating support tickets can exploit this vulnerability. The scope extends beyond the vulnerable application itself, potentially affecting the entire hosting infrastructure.

Root Cause

The root cause stems from the unrestricted use of Livewire's WithFileUploads trait in the app/Livewire/Tickets/Create.php and app/Livewire/Tickets/Show.php components. The implementation lacked proper file type validation, allowing dangerous file types to be uploaded and stored on the server. The completeUpload() function stored files without verifying their content type or extension, directly persisting user-supplied files to the public/ticket-attachments directory.

Attack Vector

The attack leverages network-accessible ticket functionality requiring only authenticated user privileges. An attacker can:

1. Authenticate to the Paymenter application with any valid user account
2. Navigate to the ticket creation or existing ticket response interface
3. Upload a malicious file (e.g., PHP web shell) as a ticket attachment
4. Access the uploaded file directly via the /storage/ path to execute arbitrary commands

The following security patch demonstrates how the vulnerability was addressed by completely removing the file upload functionality:

// Security patch in app/Livewire/Tickets/Create.php
// Source: https://github.com/Paymenter/Paymenter/commit/87c3db42282ada1e3cda54b9a01f846926c0669b

 use Illuminate\Support\Facades\Auth;
 use Illuminate\Support\Facades\RateLimiter;
 use Illuminate\Support\Facades\Storage;
-use Livewire\Features\SupportFileUploads\WithFileUploads;
 
 #[DisabledIf('tickets_disabled')]
 class Create extends Component
 {
-    use WithFileUploads;
-
-    public array $attachments = [];
-
     public string $message;
 
     public string $subject;

// Security patch in app/Livewire/Tickets/Show.php
// Source: https://github.com/Paymenter/Paymenter/commit/87c3db42282ada1e3cda54b9a01f846926c0669b

 use Illuminate\Support\Facades\Storage;
 use Livewire\Attributes\Locked;
 use Livewire\Attributes\Rule;
-use Livewire\Features\SupportFileUploads\WithFileUploads;
 
 #[DisabledIf('tickets_disabled')]
 class Show extends Component
 {
-    use WithFileUploads;
-
     #[Locked]
     public Ticket $ticket;
 
-    public array $attachments = [];
-
     #[Rule('required', 'string')]
     public string $message;
 
-    public function completeUpload($filename)
-    {
-        // Find the attachment by its name
-        foreach ($this->attachments as $key => $attachment) {
-            if ($attachment->getFilename() === $filename) {
-                $url = $attachment->store('public/ticket-attachments');
-                $url = Storage::url($url);
-
-                return url($url);
-            }
-        }
-    }

Detection Methods for CVE-2025-58048

Indicators of Compromise

• Suspicious file uploads in the /storage/public/ticket-attachments/ directory, particularly files with executable extensions (.php, .phtml, .phar)
• Unexpected web server processes spawning command-line interpreters or shells
• Unusual outbound network connections from the web server user context
• Access logs showing direct requests to files in /storage/ paths with suspicious response codes

Detection Strategies

• Monitor file system changes in the Paymenter storage directories for newly created executable files
• Implement web application firewall (WAF) rules to detect and block requests containing shell command patterns
• Analyze web server access logs for unusual POST requests to ticket creation endpoints followed by GET requests to storage paths
• Deploy file integrity monitoring on the /storage/ directory to alert on new file creation

Monitoring Recommendations

• Enable verbose logging for the Paymenter application to capture ticket attachment upload events
• Configure SIEM alerts for web shell signatures and suspicious file access patterns in storage directories
• Monitor for anomalous authentication patterns followed by ticket creation activity
• Implement egress filtering to detect potential data exfiltration attempts from the web server

How to Mitigate CVE-2025-58048

Immediate Actions Required

• Upgrade Paymenter to version 1.2.11 or later immediately
• Review the /storage/public/ticket-attachments/ directory for any suspicious or unauthorized files
• Audit user accounts for signs of compromise and reset credentials if necessary
• Check web server logs for evidence of exploitation attempts

Patch Information

The vulnerability was addressed in commit 87c3db42282ada1e3cda54b9a01f846926c0669b and released in Paymenter version 1.2.11. The patch completely removes the ticket attachments functionality by disabling the WithFileUploads trait and removing the associated code. Organizations should update immediately as there are no code modifications between version 1.2.10 and 1.2.11 other than this security fix. For detailed technical information, refer to the GitHub Security Advisory GHSA-5pm9-r2m8-rcmj.

Workarounds

• Update nginx configuration to force download of attachments instead of executing them by setting appropriate Content-Disposition headers
• Block access to the /storage/ directory entirely using a Web Application Firewall such as Cloudflare
• Implement server-side restrictions to prevent PHP execution within the storage directories
• Consider disabling the ticket system temporarily until the patch can be applied

# Nginx configuration to prevent execution of uploaded files
location /storage/ {
    # Force downloads instead of execution
    add_header Content-Disposition "attachment";
    
    # Disable PHP execution in storage directory
    location ~ \.php$ {
        deny all;
    }
}