Siemens SIMATIC S7-1500 Out-of-bounds Write (CVE-2023-6779)

high Tenable OT Security Plugin ID 503923

Synopsis

The remote OT asset is affected by a vulnerability.

Description

An off-by-one heap-based buffer 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 message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.

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: High

ID: 503923

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 11/13/2025

Updated: 11/13/2025

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v3

Risk Factor: High

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/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: 6/10/2025

Vulnerability Publication Date: 6/10/2025

Reference Information

CVE: CVE-2023-6779

CWE: 787

ICSA: 23-348-10

Detections

Analytics