Overview
In the fast-paced world of cybersecurity, vulnerabilities can pose significant threats to systems, data, and operations. One such vulnerability has been discovered in certain versions of SIMATIC PCS neo and User Management Component (UMC). Known as CVE-2025-40795, this vulnerability is a stack-based buffer overflow issue within the UMC component of the affected products. Its exploitation could lead to remote code execution or a denial of service, making it a serious issue for any organization relying on these systems. Its severity, potential impact, and widespread usage of these products underscore the necessity for immediate attention and mitigation.
Vulnerability Summary
CVE ID: CVE-2025-40795
Severity: Critical (9.8 CVSS Severity Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
SIMATIC PCS neo V4.1 | All versions
SIMATIC PCS neo V5.0 | All versions
User Management Component (UMC) | All versions < V2.15.1.3
How the Exploit Works
The CVE-2025-40795 vulnerability exists due to insufficient input validation within the integrated UMC component of the affected products. An unauthenticated attacker can exploit this vulnerability by sending specially crafted network packets to the target system. This causes a stack-based buffer overflow, which could potentially allow the attacker to execute arbitrary code or cause a denial of service condition.
Conceptual Example Code
This is a conceptual example of how an attacker might exploit the vulnerability. Please note that this is pseudocode and not meant to be executed:
POST /UMC/controller HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "malicious_payload": "A"*5000 }In this example, the attacker sends a malicious HTTP POST request to the UMC controller. The payload consists of a string of ‘A’ characters that exceeds the buffer size, causing a buffer overflow.
Mitigation Guidance
To protect against this vulnerability, it is recommended to apply the vendor-provided patch as soon as possible. Until the patch can be applied, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as a temporary mitigation. These systems can help detect and block malicious network packets that attempt to exploit the vulnerability.
