Siemens SCALANCE, RUGGEDCOM Third-Party Improper Input Validation (CVE-2021-26401)

medium Tenable OT Security Plugin ID 503283

Synopsis

The remote OT asset is affected by a vulnerability.

Description

LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original can be found at CISA.gov.

Siemens has identified the following specific workarounds and mitigations users can apply to reduce risk:
- Update all of the affected products to v7.2 or later version or the software.

As a general security measure, Siemens strongly recommends users protect network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends users configure the environment according to Siemens' operational guidelines for Industrial Security, and to follow the recommendations in the product manuals. Additional information on Industrial Security by Siemens can be found on the Siemens page for Industrial Security.

For further inquiries on security vulnerabilities in Siemens products and solutions, contact the Siemens ProductCERT. For more information, see the associated Siemens security advisory SSA-419740 in HTML and CSAF.

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-419740.pdf

https://support.industry.siemens.com/cs/document/109817007/

https://www.cisa.gov/news-events/ics-advisories/icsa-23-075-01

Plugin Details

Severity: Medium

ID: 503283

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 7/8/2025

Updated: 7/8/2025

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v3

Risk Factor: Medium

Base Score: 5.6

Temporal Score: 5.1

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

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

Vulnerability Information

CPE: cpe:/o:siemens:scalance_m804pb_firmware:7.2, cpe:/o:siemens:scalance_m816-1_adsl-router_%28annex_a%29_firmware:7.2, cpe:/o:siemens:scalance_m874-3_firmware:7.2, cpe:/o:siemens:scalance_m876-4_%28nam%29_firmware:7.2, cpe:/o:siemens:scalance_s615_eec_firmware:7.2, cpe:/o:siemens:scalance_m876-3_%28evdo%29_firmware:7.2, cpe:/o:siemens:scalance_m816-1_adsl-router_%28annex_b%29_firmware:7.2, cpe:/o:siemens:scalance_s615_firmware:7.2, cpe:/o:siemens:ruggedcom_rm1224_lte%284g%29_eu_firmware:7.2, cpe:/o:siemens:scalance_m812-1_adsl-router_%28annex_a%29_firmware:7.2, cpe:/o:siemens:scalance_mum856-1_%28row%29_firmware:7.2, cpe:/o:siemens:scalance_m812-1_adsl-router_%28annex_b%29_firmware:7.2, cpe:/o:siemens:scalance_mum853-1_%28eu%29_firmware:7.2, cpe:/o:siemens:scalance_m874-2_firmware:7.2, cpe:/o:siemens:ruggedcom_rm1224_lte%284g%29_nam_firmware:7.2, cpe:/o:siemens:scalance_m876-4_%28eu%29_firmware:7.2, cpe:/o:siemens:scalance_m826-2_shdsl-router_firmware:7.2, cpe:/o:siemens:scalance_mum856-1_%28eu%29_firmware:7.2, cpe:/o:siemens:scalance_m876-4_firmware:7.2, cpe:/o:siemens:scalance_m876-3_%28rok%29_firmware:7.2

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 3/14/2023

Vulnerability Publication Date: 3/14/2023

Reference Information

CVE: CVE-2021-26401

CWE: 20

ICSA: 23-075-01