Siemens SIMATIC S7-1500 Incorrect Calculation of Buffer Size (CVE-2023-6780)

medium Tenable OT Security Plugin ID 503947

Synopsis

The remote OT asset is affected by a vulnerability.

Description

An integer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a very long message, leading to an incorrect calculation of the buffer size to store the message, resulting in undefined behavior. This issue affects glibc 2.37 and newer.

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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 is preparing fixed versions and reports that currently, no fix is available.

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-082556 in HTML and CSAF.

Plugin Details

Severity: Medium

ID: 503947

File Name: tenable_ot_siemens_CVE-2023-6780.nasl

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 11/13/2025

Updated: 2/14/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 2.2

CVSS v3

Risk Factor: Medium

Base Score: 5.3

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

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: 6/10/2025

Vulnerability Publication Date: 6/10/2025

Reference Information

CVE: CVE-2023-6780

CWE: 131

ICSA: 23-348-10, 25-162-05

Detections

Analytics