Siemens SCALANCE and RUGGEDCOM Devices Improper Input Validation (CVE-2024-49858)

medium Tenable OT Security Plugin ID 504581

Synopsis

The remote OT asset is affected by a vulnerability.

Description

efistub/tpm: Use ACPI reclaim memory for event log to avoid corruption The TPM event log table is a Linux specific construct, where the data produced by the GetEventLog() boot service is cached in memory, and passed on to the OS using an EFI configuration table. The use of EFI_LOADER_DATA here results in the region being left unreserved in the E820 memory map constructed by the EFI stub, and this is the memory description that is passed on to the incoming kernel by kexec, which is therefore unaware that the region should be reserved. Even though the utility of the TPM2 event log after a kexec is questionable, any corruption might send the parsing code off into the weeds and crash the kernel.

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.

Plugin Details

Severity: Medium

ID: 504581

File Name: tenable_ot_siemens_CVE-2024-49858.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-2024-49858

CWE: 20

ICSA: 25-226-07

Detections

Analytics