Siemens LOGO! 8 BM Use of Hard-Coded Cryptographic Key (CVE-2020-25234)

high Tenable OT Security Plugin ID 501680

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability has been identified in LOGO! 8 BM (incl. SIPLUS variants) (All versions < V8.3), LOGO! Soft Comfort (All versions < V8.3). The LOGO! program files generated and used by the affected components offer the possibility to save user-defined functions (UDF) in a password protected way. This protection is implemented in the software that displays the information. An attacker could reverse engineer the UDFs directly from stored program files.

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 released updates for the affected products and recommends users update to the latest versions:

- LOGO! 8 BM (incl. SIPLUS variants): Update to v8.3; A new hardware version is required in order to update
- LOGO! Soft Comfort: Update to v8.3

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

- Protect access to Port 10005/TCP
- Apply defense-in-depth concept, including protection concept outlined in the system manual.

As a general security measure, Siemens strongly recommends users protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends users 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 more information, please see Siemens Security Advisory SSA-480824

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-480824.pdf

https://www.cisa.gov/news-events/ics-advisories/icsa-20-343-10

Plugin Details

Severity: High

ID: 501680

Version: 1.4

Type: remote

Family: Tenable.ot

Published: 9/21/2023

Updated: 3/4/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 5.2

CVSS v2

Risk Factor: Low

Base Score: 3.6

Temporal Score: 2.7

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

CVSS Score Source: CVE-2020-25234

CVSS v3

Risk Factor: High

Base Score: 7.7

Temporal Score: 6.7

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

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

Vulnerability Information

CPE: cpe:/o:siemens:logo%21_8_bm_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 12/14/2020

Vulnerability Publication Date: 12/14/2020

Reference Information

CVE: CVE-2020-25234

CWE: 321