Siemens SIMATIC and SCALANCE Devices Improper Input Validation (CVE-2023-31436)

high Tenable OT Security Plugin ID 503822

Synopsis

The remote OT asset is affected by a vulnerability.

Description

qfq_change_class in net/sched/sch_qfq.c in the Linux kernel before 6.2.13 allows an out-of-bounds write because lmax can exceed QFQ_MIN_LMAX.

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: 503822

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 10/29/2025

Updated: 10/29/2025

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:siemens:scalance_xcm332_firmware:2.4, cpe:/o:siemens:scalance_xrh334_%2824_v_dc%2c_8xfo%2c_cc%29_firmware:2.4, cpe:/o:siemens:scalance_xrm334_%28230_v_ac%2c_8xfo%29_firmware:2.4, cpe:/o:siemens:scalance_xch328_firmware:2.4, cpe:/o:siemens:simatic_s7-1500_tm_mfp_firmware, cpe:/o:siemens:scalance_xrm334_%2824_v_dc%2c_12xfo%29_firmware:2.4, cpe:/o:siemens:scalance_xrm334_%2824_v_dc%2c_8xfo%29_firmware:2.4, cpe:/o:siemens:scalance_xrm334_%282x230_v_ac%2c_12xfo%29_firmware:2.4, cpe:/o:siemens:scalance_xrm334_%28230_v_ac%2c_12xfo%29_firmware:2.4, cpe:/o:siemens:scalance_xrm334_%282x230_v_ac%2c_8xfo%29_firmware:2.4, cpe:/o:siemens:scalance_xcm328_firmware:2.4, cpe:/o:siemens:scalance_xcm324_firmware:2.4

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 6/13/2023

Vulnerability Publication Date: 6/13/2023

Reference Information

CVE: CVE-2023-31436

CWE: 20

Detections

Analytics