Siemens SIMATIC S7-1500 TM MFP Improper Input Validation (CVE-2026-43093)

high Tenable OT Security Plugin ID 506444

Synopsis

The remote OT asset is affected by a vulnerability.

Description

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

xsk: tighten UMEM headroom validation to account for tailroom and min frame

The current headroom validation in xdp_umem_reg() could leave us with insufficient space dedicated to even receive minimum-sized ethernet frame. Furthermore if multi-buffer would come to play then skb_shared_info stored at the end of XSK frame would be corrupted.

HW typically works with 128-aligned sizes so let us provide this value as bare minimum.

Multi-buffer setting is known later in the configuration process so besides accounting for 128 bytes, let us also take care of tailroom space upfront.

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: High

ID: 506444

File Name: tenable_ot_siemens_CVE-2026-43093.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: 4.9

Percentile: 58.09

CVSS v3

Risk Factor: High

Base Score: 7.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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-2026-43093

CWE: 20