Siemens SIMATIC S7-1500 TM MFP Improper Input Validation (CVE-2026-53149)

high Tenable OT Security Plugin ID 506278

Synopsis

The remote OT asset is affected by a vulnerability.

Description

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

thunderbolt: Bound root directory content to block size

__tb_property_parse_dir() does not check that content_offset + content_len fits within block_len for the root directory case.
When rootdir->length equals or exceeds block_len - 2, the entry loop reads past the allocated property block.

Add a bounds check after computing content_offset and content_len to reject directories whose content extends past the block.

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: 506278

File Name: tenable_ot_siemens_CVE-2026-53149.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: Medium

Score: 6.3

Percentile: 96.34

CVSS v3

Risk Factor: High

Base Score: 7.1

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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-2026-53149

CWE: 20

Detections

Analytics