Siemens SIMATIC and SCALANCE Products Encryption Strength (CVE-2023-0464)

high Tenable OT Security Plugin ID 502324

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A security vulnerability has been identified in all supported versions of OpenSSL related to the verification of X.509 certificate chains that include policy constraints. Attackers may be able to exploit this vulnerability by creating a malicious certificate chain that triggers exponential use of computational resources, leading to a denial-of-service (DoS) attack on affected systems.

Policy processing is disabled by default but can be enabled by passing the '-policy' argument to the command line utilities or by calling the X509_VERIFY_PARAM_set1_policies() function.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Siemens has identified the following specific workarounds and mitigations that customers can apply to reduce the risk:
- Only build and run applications from trusted sources.

See Also

https://www.openssl.org/news/secadv/20230207.txt

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

https://cert-portal.siemens.com/productcert/html/ssa-794697.html

https://cert-portal.siemens.com/productcert/html/ssa-625862.html

https://cert-portal.siemens.com/productcert/html/ssa-879734.html

https://www.cisa.gov/news-events/ics-advisories/icsa-24-165-10

https://www.cisa.gov/news-events/ics-advisories/icsa-24-165-11

Plugin Details

Severity: High

ID: 502324

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 7/23/2024

Updated: 7/23/2024

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:siplus_et_200sp_cp_1542sp-1_irc_tx_rail_firmware, cpe:/o:siemens:siplus_et_200sp_cp_1543sp-1_isec_firmware, cpe:/o:siemens:simatic_s7-1500_firmware, cpe:/o:siemens:scalance_xm416-4c_firmware, cpe:/o:siemens:scalance_xr524-8c_firmware, cpe:/o:siemens:simatic_cp_1543sp-1_firmware, cpe:/o:siemens:scalance_xm408-4c_firmware, cpe:/o:siemens:simatic_s7-1500_tm_mfp, cpe:/o:siemens:simatic_cp_1542sp-1_firmware, cpe:/o:siemens:siplus_et_200sp_cp_1543sp-1_isec_tx_rail_firmware, cpe:/o:siemens:scalance_xr526-8c_firmware, cpe:/o:siemens:scalance_xm408-8c_firmware, cpe:/o:siemens:scalance_xr552-12m_firmware, cpe:/o:siemens:simatic_cp_1542sp-1_irc_firmware, cpe:/o:siemens:scalance_xr528-6m_firmware

Required KB Items: Tenable.ot/Siemens

Patch Publication Date: 1/10/2023

Vulnerability Publication Date: 1/10/2023

Reference Information

CVE: CVE-2023-0464

CWE: 326