Siemens SIMATIC and SCALANCE Products Inadequate Encryption Strength (CVE-2023-0466)

medium Tenable OT Security Plugin ID 502325

Synopsis

The remote OT asset is affected by a vulnerability.

Description

The function X509_VERIFY_PARAM_add0_policy() is documented to implicitly enable the certificate policy check when doing certificate verification. However the implementation of the function does not enable the check which allows certificates with invalid or incorrect policies to pass the certificate verification.

As suddenly enabling the policy check could break existing deployments it was decided to keep the existing behavior of the X509_VERIFY_PARAM_add0_policy() function.

Instead the applications that require OpenSSL to perform certificate policy check need to use X509_VERIFY_PARAM_set1_policies() or explicitly enable the policy check by calling X509_VERIFY_PARAM_set_flags() with the X509_V_FLAG_POLICY_CHECK flag argument.

Certificate policy checks are disabled by default in OpenSSL and are not commonly used by applications.

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

Solution

The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original can be found at CISA.gov.

Siemens has identified the following specific workarounds and mitigations users can apply to reduce risk:

- SIMATIC S7-1500 TM MFP - Linux Kernel: Only build and run applications from trusted sources. Currently no patch is available.

As a general security measure, Siemens strongly recommends to protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens' operational guidelines for Industrial Security and to follow the recommendations in the product manuals. Additional information on Industrial Security by Siemens can be found at:
https://www.siemens.com/industrialsecurity.

For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the Siemens ProductCERT: https://www.siemens.com/cert/advisories.

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-794697 in HTML and CSAF.

Plugin Details

Severity: Medium

ID: 502325

Version: 1.5

Type: remote

Family: Tenable.ot

Published: 7/23/2024

Updated: 9/4/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 2.2

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

CVSS Score Source: CVE-2023-0466

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

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

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

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

Exploit Ease: No known exploits are available

Patch Publication Date: 1/10/2023

Vulnerability Publication Date: 1/10/2023

Reference Information

CVE: CVE-2023-0466

CWE: 326

ICSA: 23-166-11, 24-165-10, 24-165-11

Detections

Analytics