CVE-2025-40737: Critical File Path Validation Vulnerability in SINEC NMS

Overview

A new vulnerability, designated as CVE-2025-40737, has been discovered in SINEC NMS – a widely used network management system. This vulnerability poses a critical risk to all versions of the software prior to version V4.0, potentially impacting a significant number of networks and systems worldwide. The gravity of this vulnerability lies in its ability to allow an attacker to write arbitrary files to restricted locations, thereby potentially executing code with elevated privileges. Its exploitation could lead to system compromise or data leakage, making it a high priority issue for all SINEC NMS users.

Vulnerability Summary

CVE ID: CVE-2025-40737
Severity: Critical, CVSS Score 8.8
Attack Vector: Network
Privileges Required: Low
User Interaction: None
Impact: System compromise and potential data leakage

Affected Products

Product | Affected Versions

SINEC NMS | All versions < V4.0 How the Exploit Works

The vulnerability stems from the application’s inadequate validation of file paths when extracting uploaded ZIP files. An attacker can exploit this by crafting a malicious ZIP file with a specific file path that points to a restricted location. Once the ZIP file is uploaded and extracted, the attacker’s files are written to the restricted location. Depending on the permissions of the files and the locations they are written to, the attacker could potentially execute code with elevated privileges.

Conceptual Example Code

Below is a
conceptual
example of how the vulnerability might be exploited. This is a sample HTTP request, demonstrating the upload of a malicious ZIP file.

POST /upload/zip HTTP/1.1
Host: target.example.com
Content-Type: application/zip
Content-Disposition: attachment; filename=malicious.zip
{ "malicious_payload": "..." }

In the above request, the “malicious_payload” would be a ZIP file crafted to exploit the vulnerability. The file would contain malicious files with paths designed to overwrite files or write to restricted locations.

Mitigation

Users are urged to apply the vendor’s patch as soon as possible. Until the patch can be applied, users should implement a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation measure to detect and block attempts to exploit this vulnerability.
Please remember that while WAFs and IDS systems provide a layer of defense, they are not a substitute for patching and updating systems. Always prioritize updating and patching vulnerable systems to maintain a robust security posture.