Siemens SIMATIC S7-1500 CPU 1518 MFP Improper Input Validation (CVE-2026-4438)

medium Tenable OT Security Plugin ID 505729

Synopsis

The remote OT asset is affected by a vulnerability.

Description

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Refer to the vendor advisory.

Plugin Details

Severity: Medium

ID: 505729

File Name: tenable_ot_siemens_CVE-2026-4438.nasl

Version: 1.1

Type: Remote

Family: Tenable.ot

Published: 7/27/2026

Updated: 7/27/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 2.1

Percentile: 7.86

CVSS v3

Risk Factor: Medium

Base Score: 5.4

Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Vulnerability Information

CPE: cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.1.5, cpe:/o:siemens:siplus_s7-1500_cpu_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 6/10/2025

Vulnerability Publication Date: 3/20/2026

Reference Information

CVE: CVE-2026-4438

CWE: 20

Detections

Analytics