Siemens SIMATIC S7-1500 TM MFP BIOS Integer Overflow or Wraparound (CVE-2021-35942)

critical Tenable OT Security Plugin ID 502942

Synopsis

The remote OT asset is affected by a vulnerability.

Description

The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations.

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.

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-831302.pdf

https://cert-portal.siemens.com/productcert/html/ssa-398330.html

https://support.industry.siemens.com/cs/ww/en/view/109945851/

https://www.cisa.gov/news-events/ics-advisories/icsa-23-166-10

Plugin Details

Severity: Critical

ID: 502942

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 2/25/2025

Updated: 2/25/2025

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 5.2

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 8.2

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

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:siemens:simatic_s7-1500_tm_mfp, cpe:/o:siemens:siplus_s7-1500_cpu_firmware:3.1.0, cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.1.0

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-2021-35942

CWE: 190

ICSA: 23-166-10