Siemens SCALANCE X Switches Insufficient Resource Pool (CVE-2019-10942)

high Tenable OT Security Plugin ID 501046

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability has been identified in SCALANCE X-200 switch family (incl. SIPLUS NET variants) (All versions < V5.2.5), SCALANCE X-200IRT switch family (incl. SIPLUS NET variants) (All versions < V5.5.0), SCALANCE X204RNA (HSR) (All versions), SCALANCE X204RNA (PRP) (All versions), SCALANCE X204RNA EEC (HSR) (All versions), SCALANCE X204RNA EEC (PRP) (All versions), SCALANCE X204RNA EEC (PRP/HSR) (All versions). The device contains a vulnerability that could allow an attacker to trigger a denial-of-service condition by sending large message packages repeatedly to the telnet service. The security vulnerability could be exploited by an attacker with network access to the affected systems. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise availability of the device.

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 updates, workarounds and mitigations users can apply to reduce the risk:

- SCALANCE X-200 switch family (incl. SIPLUS NET variants): Update to v5.2.5 or later
- SCALANCE X-200IRT switch family (incl. SIPLUS NET variants): Update to v5.5.0 or later
- Disable telnet service on affected devices. Users should use SSH instead.
- Restrict network access to Port 23/TCP of the device.

Siemens recommends users configure their environment according to Siemens’ operational guidelines for industrial security and 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 on the vulnerability and more detailed mitigation instructions, please see Siemens security advisory SSA-100232

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-100232.pdf

https://www.cisa.gov/news-events/ics-advisories/icsa-19-225-03

Plugin Details

Severity: High

ID: 501046

Version: 1.6

Type: remote

Family: Tenable.ot

Published: 4/11/2023

Updated: 3/4/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2019-10942

CVSS v3

Risk Factor: High

Base Score: 8.6

Temporal Score: 7.5

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

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

Vulnerability Information

CPE: cpe:/o:siemens:scalance_x-200_series_firmware, cpe:/o:siemens:scalance_x-200irt_series_firmware, cpe:/o:siemens:scalance_x-204rna_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 8/13/2019

Vulnerability Publication Date: 8/13/2019

Reference Information

CVE: CVE-2019-10942

CWE: 400