Siemens SCALANCE and RUGGEDCOM Devices Improper Input Validation (CVE-2024-46840)

medium Tenable OT Security Plugin ID 504660

Synopsis

The remote OT asset is affected by a vulnerability.

Description

btrfs: clean up our handling of refs == 0 in snapshot delete. In reada we BUG_ON(refs == 0), which may be problematic because there is no lock on the extent leave, potentially leading to a transient incorrect answer. In walk_down_proc, BUG_ON(refs == 0) is also used, which could occur due to extent tree corruption. This has been changed to return
-EUCLEAN. In do_walk_down() this case is caught and handled correctly, however -EIO is returned, whereas -EUCLEAN would a more appropriate error code. Finally in walk_up_proc, BUG_ON(refs == 0) is also used, it has also been converted to proper error handling.

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:

- All affected products: Update to V3.2 or later version

As a general security measure, Siemens recommends protecting network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens' operational guidelines for industrial security and following recommendations in the product manuals.

Additional information on industrial security by Siemens can be found on the Siemens industrial security webpage

For more information see the associated Siemens security advisory SSA-355557 in HTML and CSAF.

See Also

https://cert-portal.siemens.com/productcert/html/ssa-355557.html

https://support.industry.siemens.com/cs/ww/en/view/109988839/

https://www.cisa.gov/news-events/ics-advisories/ICSA-25-226-07

Plugin Details

Severity: Medium

ID: 504660

File Name: tenable_ot_siemens_CVE-2024-46840.nasl

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 11/18/2025

Updated: 2/12/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/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_xrh-300_series_firmware, cpe:/o:siemens:scalance_xc-300_series_firmware, cpe:/o:siemens:scalance_xc-400_series_firmware, cpe:/o:siemens:scalance_xch-300_series_firmware, cpe:/o:siemens:scalance_xrm-300_series_firmware, cpe:/o:siemens:scalance_xcm-300_series_firmware, cpe:/o:siemens:scalance_xr-500_series_firmware, cpe:/o:siemens:ruggedcom_rst2428p_firmware:3.2, cpe:/o:siemens:scalance_xr-500wg_series_firmware, cpe:/o:siemens:scalance_xr-300_series_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 8/12/2025

Vulnerability Publication Date: 8/12/2025

Reference Information

CVE: CVE-2024-46840

CWE: 20

ICSA: 25-226-07