Siemens SIMATIC Devices NULL Pointer Dereference (CVE-2023-3772)

medium Tenable OT Security Plugin ID 503824

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A flaw was found in the Linux kernel's IP framework for transforming packets (XFRM subsystem). This issue may allow a malicious user with CAP_NET_ADMIN privileges to directly dereference a NULL pointer in xfrm_update_ae_params(), leading to a possible kernel crash and denial of service.

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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:

- SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0): Only build and run applications from trusted sources.
Currently no fix is available.
- SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0): Only build and run applications from trusted sources.
Currently no fix is available.
- SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0): Only build and run applications from trusted sources.
Currently no fix is available.
- SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0): Only build and run applications from trusted sources.
Currently no fix is available.
- SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0): Only build and run applications from trusted sources.
Currently no fix is available.

Note: This SSA advises vulnerabilities for firmware version V3.1 only; for versions prior to V3.1 refer to SiemensSecurity Bulletin SSB-439005.

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-398330 in HTML and CSAF.

Plugin Details

Severity: Medium

ID: 503824

File Name: tenable_ot_siemens_CVE-2023-3772.nasl

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 10/29/2025

Updated: 2/14/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v3

Risk Factor: Medium

Base Score: 5.5

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

Vulnerability Information

CPE: cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.1.5, cpe:/o:siemens:siplus_s7-1500_cpu_firmware:3.1.5, cpe:/o:siemens:simatic_s7-1500_tm_mfp_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 6/13/2023

Vulnerability Publication Date: 6/13/2023

Reference Information

CVE: CVE-2023-3772

CWE: 476

ICSA: 23-348-10

Detections

Analytics