Siemens SIMATIC S7-1500 TM MFP Improper Input Validation (CVE-2026-53131)

critical Tenable OT Security Plugin ID 506423

Synopsis

The remote OT asset is affected by a vulnerability.

Description

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

netfilter: require Ethernet MAC header before using eth_hdr()

`ip6t_eui64`, `xt_mac`, the `bitmap:ip,mac`, `hash:ip,mac`, and `hash:mac` ipset types, and `nf_log_syslog` access `eth_hdr(skb)` after either assuming that the skb is associated with an Ethernet device or checking only that the `ETH_HLEN` bytes at `skb_mac_header(skb)` lie between `skb->head` and `skb->data`.

Make these paths first verify that the skb is associated with an Ethernet device, that the MAC header was set, and that it spans at least a full Ethernet header before accessing `eth_hdr(skb)`.

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: Critical

ID: 506423

File Name: tenable_ot_siemens_CVE-2026-53131.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: 4.5

Percentile: 57.62

CVSS v3

Risk Factor: Critical

Base Score: 9.4

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/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-2026-53131

CWE: 20

Detections

Analytics