Siemens SIMATIC S7-1500 CPU 1518 MFP Write-what-where Condition (CVE-2026-43284)

high Tenable OT Security Plugin ID 505598

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: High

ID: 505598

File Name: tenable_ot_siemens_CVE-2026-43284.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: Critical

Score: 9.5

Percentile: 99.86

CVSS v3

Risk Factor: High

Base Score: 8.8

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

Vulnerability Information

CPE: cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.1.5, cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.1.6, cpe:/o:siemens:siplus_s7-1500_cpu_firmware, cpe:/o:siemens:siplus_s7-1500_cpu_firmware:3.1.6

Required KB Items: Tenable.ot/Siemens

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 6/10/2025

Vulnerability Publication Date: 5/8/2026

Reference Information

CVE: CVE-2026-43284

CWE: 123

Detections

Analytics