Siemens SIMATIC Devices Improper Input Validation (CVE-2025-21756)

high Tenable OT Security Plugin ID 503431

Synopsis

The remote OT asset is affected by a vulnerability.

Description

vsock: Keep the binding until socket destruction Preserve sockets bindings; this includes both resulting from an explicit bind() and those implicitly bound through autobind during connect().

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: 503431

Version: 1.3

Type: remote

Family: Tenable.ot

Published: 10/27/2025

Updated: 10/30/2025

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Critical

Score: 9.2

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.5

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

Temporal Vector: CVSS:3.0/E:H/RL:O/RC:C

Vulnerability Information

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

Required KB Items: Tenable.ot/Siemens

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/9/2024

Vulnerability Publication Date: 4/9/2024

Reference Information

CVE: CVE-2025-21756

CWE: 20

Detections

Analytics