Siemens SIMATIC S7-1500 Use After Free (CVE-2021-20227)

medium Tenable OT Security Plugin ID 504118

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A flaw was found in SQLite's SELECT query functionality (src/select.c). This flaw allows an attacker who is capable of running SQL queries locally on the SQLite database to cause a denial of service or possible code execution by triggering a use-after-free. The highest threat from this vulnerability is to system availability.

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: Medium

ID: 504118

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 11/13/2025

Updated: 11/14/2025

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

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 12/12/2023

Vulnerability Publication Date: 12/12/2023

Reference Information

CVE: CVE-2021-20227

CWE: 416

Detections

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