Siemens SCALANCE and RUGGEDCOM Use After Free (CVE-2025-4516)

medium Tenable OT Security Plugin ID 505133

Synopsis

The remote OT asset is affected by a vulnerability.

Description

There is an issue in CPython when using `bytes.decode(unicode_escape, error=ignore|replace)`. If you are not using the unicode_escape encoding or an error handler your usage is not affected. To work-around this issue you may stop using the error= handler and instead wrap the bytes.decode() call in a try- except catching the DecodeError.

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: 505133

File Name: tenable_ot_siemens_CVE-2025-4516.nasl

Version: 1.3

Type: remote

Family: Tenable.ot

Published: 2/10/2026

Updated: 3/5/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v3

Risk Factor: Medium

Base Score: 5.1

Temporal Score: 4.5

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

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

Vulnerability Information

CPE: cpe:/o:siemens:scalance_xrm334_%28230v_ac%2c_2x10g%2c_24xsfp%2c_8xsfp%2b%29_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%282x230_v_ac%2c_8xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%28230_v_ac%2c_8xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%2824_v_dc%2c_8xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xr-500wg_series_firmware, cpe:/o:siemens:scalance_xrm334_%282x230_v_ac%2c_12xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xch328_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%2824v_dc%2c_2x10g%2c_24xsfp%2c_8xsfp%2b%29_firmware:3.3, cpe:/o:siemens:scalance_xc-300_series_firmware, cpe:/o:siemens:scalance_xc-400_series_firmware, cpe:/o:siemens:scalance_xcm328_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%28230_v_ac%2c_12xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%282x230v_ac%2c_2x10g%2c_24xsfp%2c_8xsfp%2b%29_firmware:3.3, cpe:/o:siemens:ruggedcom_rst2428p_firmware:3.3, cpe:/o:siemens:scalance_xr-300_series_firmware, cpe:/o:siemens:scalance_xcm324_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%2824_v_dc%2c_12xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xr-500_series_firmware, cpe:/o:siemens:scalance_xrh334_%2824_v_dc%2c_8xfo%2c_cc%29_firmware:3.3, cpe:/o:siemens:scalance_xcm332_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 1/28/2026

Vulnerability Publication Date: 5/15/2025

Reference Information

CVE: CVE-2025-4516

CWE: 416

ICSA: 26-043-06

Detections

Analytics