Siemens SIMATIC S7-1500 TM MFP Improper Input Validation (CVE-2026-53150)

medium Tenable OT Security Plugin ID 506369

Synopsis

The remote OT asset is affected by a vulnerability.

Description

In the Linux kernel, the following vulnerability has been resolved:

thunderbolt: Reject zero-length property entries in validator

tb_property_entry_valid() accepts entries with length == 0 for DIRECTORY, DATA, and TEXT types. A zero-length TEXT entry passes validation but causes an underflow in the null-termination logic:

property->value.text[property->length * 4 - 1] = '\\0';

When property->length is 0 this writes to offset -1 relative to the allocation.

Reject zero-length entries early in the validator since they have no valid representation in the XDomain property protocol.

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.

See Also

https://cert-portal.siemens.com/productcert/html/ssa-784472.html

Plugin Details

Severity: Medium

ID: 506369

File Name: tenable_ot_siemens_CVE-2026-53150.nasl

Version: 1.1

Type: Remote

Family: Tenable.ot

Published: 10/20/2026

Updated: 10/20/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.75

CVSS v3

Risk Factor: Medium

Base Score: 5.5

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

Vulnerability Information

CPE: cpe:/o:siemens:simatic_s7-1500_tm_mfp

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 10/13/2026

Vulnerability Publication Date: 10/13/2026

Reference Information

CVE: CVE-2026-53150

CWE: 20