Siemens SIMATIC S7-1500 TM MFP Improper Input Validation (CVE-2026-45838)

medium Tenable OT Security Plugin ID 506370

Synopsis

The remote OT asset is affected by a vulnerability.

Description

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

bpf: fix end-of-list detection in cgroup_storage_get_next_key()

list_next_entry() never returns NULL -- when the current element is the last entry it wraps to the list head via container_of(). The subsequent NULL check is therefore dead code and get_next_key() never returns
-ENOENT for the last element, instead reading storage->key from a bogus pointer that aliases internal map fields and copying the result to userspace.

Replace it with list_entry_is_head() so the function correctly returns
-ENOENT when there are no more entries.

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: Medium

ID: 506370

File Name: tenable_ot_siemens_CVE-2026-45838.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: 5

Percentile: 94.14

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-2026-45838

CWE: 20

Detections

Analytics