Siemens SCALANCE and RUGGEDCOM Improper Input Validation (CVE-2025-39839)

high Tenable OT Security Plugin ID 505117

Synopsis

The remote OT asset is affected by a vulnerability.

Description

In the Linux kernel, the following vulnerability has been resolved:
batman-adv: fix OOB read/write in network-coding decode batadv_nc_skb_decode_packet() trusts coded_len and checks only against skb->len. XOR starts at sizeof(struct batadv_unicast_packet), reducing payload headroom, and the source skb length is not verified, allowing an out-of-bounds read and a small out-of-bounds write. Validate that coded_len fits within the payload area of both destination and source sk_buffs before XORing.

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: 505117

File Name: tenable_ot_siemens_CVE-2025-39839.nasl

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 2/10/2026

Updated: 2/11/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 6.0

CVSS v2

Risk Factor: Medium

Base Score: 6.2

Temporal Score: 4.6

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:N/A:C

CVSS Score Source: CVE-2025-39839

CVSS v3

Risk Factor: High

Base Score: 7.1

Temporal Score: 6.2

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

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

Vulnerability Information

CPE: cpe:/o:siemens:scalance_xrm334_%28230_v_ac%2c_8xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xcm324_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_xrm334_%2824_v_dc%2c_8xfo%29_firmware:3.3, 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_%2824_v_dc%2c_12xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xrm334_%28230v_ac%2c_2x10g%2c_24xsfp%2c_8xsfp%2b%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:scalance_xrm334_%282x230_v_ac%2c_8xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xrh334_%2824_v_dc%2c_8xfo%2c_cc%29_firmware:3.3, cpe:/o:siemens:ruggedcom_rst2428p_firmware:3.3, cpe:/o:siemens:scalance_xcm332_firmware, cpe:/o:siemens:scalance_xrm334_%282x230_v_ac%2c_12xfo%29_firmware:3.3, cpe:/o:siemens:scalance_xch328_firmware:3.3

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 1/28/2026

Vulnerability Publication Date: 9/19/2025

Reference Information

CVE: CVE-2025-39839

CWE: 20

Detections

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