CVE-2021-46386

Vulnerability

A file upload vulnerability exists in the net.mingsoft.basic.action.web.FileAction#upload endpoint of mingSoft MCMS through version 5.2.5 [1][2]. The application fails to properly validate uploaded file types, allowing an attacker to upload a malicious .jspx file that can be executed by the server.

Exploitation

An unauthenticated remote attacker can exploit this vulnerability by sending a crafted HTTP request to the upload endpoint with a .jspx webshell payload [4]. No special privileges or user interaction are required; the attacker only needs network access to the vulnerable MCMS instance.

Impact

Successful exploitation results in remote code execution (RCE) with the privileges of the web server process. This allows the attacker to execute arbitrary commands, access sensitive data, modify application files, and potentially pivot to other systems on the network.

Mitigation

As of the publication date, no official patch has been released for this vulnerability [2][4]. Users are advised to upgrade to a version beyond 5.2.5 if available, or implement strict file type validation and access controls on the upload endpoint. The issue is tracked in the project's issue tracker [4].